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Model infoModelsSnapshot: 15 Oct 2026

Fish Audio / S2.1

Fish Audio S2.1 Pro

Multilingual speech synthesis with natural-language delivery controls, voice conditioning and multi-speaker dialogue. Paid and free API tiers use the same model.

availableClosed weightsText-to-speech
Official documentation (opens in a new tab)Reviewed 13 Oct 2026
12 of 23 specification fields collected
Output formatsWAV, PCM, MP3, OpusSee specification notes below
Languages83 languages with automatic language detectionSee specification notes below
Input billingSee ratesFish Audio API
Output billingSee ratesPublished units and conditions below

Specifications

Provider-documented facts. “Not collected” means we have not verified that field yet, not that the feature is unsupported.

Context / input limit
Not collected
Maximum output
Not collected
Input modalities
Text, AudioSource for Input modalities (opens in a new tab)

Audio is optional voice-conditioning input, not arbitrary audio understanding.

Reasoning
Not collected
Tool calling
Not collected
Structured output
Not collected
Batch processing
Not collected
Fine-tuning
Not collected
Knowledge cutoff
Not collected
Parameters
Not collected
Architecture
Not collected
Languages
83 languages with automatic language detectionSource for Languages (opens in a new tab)
Context caching
Not collected
Equivalent API aliases
s2.1-pro, s2.1-pro-freeSource for Equivalent API aliases (opens in a new tab)

The free selector is an access tier, not another model.

Output formats
WAV, PCM, MP3, OpusSource for Output formats (opens in a new tab)
Audio sample rates
Default 44,100 Hz for most formats; 48,000 Hz for OpusSource for Audio sample rates (opens in a new tab)
Generation controls
Text chunks 100–300 characters; min chunk 0–100. max_new_tokens defaults to 1,024 audio tokens per chunk. Temperature/top_p 0–1; latency normal/balanced/lowSource for Generation controls (opens in a new tab)

Chunk controls are not total input or output limits. Internal batching is not a public batch API.

Voice cloning
Library voice IDs or reference audio with transcripts; persistent private voice profiles can be created separatelySource for Voice cloning (opens in a new tab)

Recommended recording duration is guidance, not an established hard request limit. Cloning does not prove base-model fine-tuning.

Audio controls
Open-ended bracketed natural-language delivery controls and multi-speaker dialogueSource for Audio controls (opens in a new tab)
Published price
$15 per 1M UTF-8 input bytes; separate free development tierSource for Published price (opens in a new tab)

Access & pricing

Prices belong to an endpoint and billing tier. A provider listing does not guarantee access for every account or region.

API model ID
s2.1-pro
Access
Production API access; account balance, rate limits and contractual terms apply.
Regions
Processing region and residency not established for this access path.
API endpoint URL
https://api.fish.audio/v1/ttsSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
Raw audio responseSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M UTF-8 bytes

Rate conditions

  1. Native input text measured in UTF-8 bytes, not Unicode characters or LLM tokens. Pay as you go without a monthly minimum. S1 pricing applies before its scheduled replacement.
Pricing source (opens in a new tab)

Data & enterprise terms

Fish Audio terms permit Usage Data and Content to improve its models, including third-party components. Public terms do not establish universal zero retention. Free S2.1 has no DPA or TTFA guarantees; confirm production contractual terms separately. Voice inputs require appropriate rights.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro
Access
Production API access; account balance, rate limits and contractual terms apply.
Regions
Processing region and residency not established for this access path.
API endpoint URL
https://api.fish.audio/v1/tts/stream/with-timestampSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
SSE audio with word timestampsSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M UTF-8 bytes

Rate conditions

  1. Native input text measured in UTF-8 bytes, not Unicode characters or LLM tokens. Pay as you go without a monthly minimum. S1 pricing applies before its scheduled replacement.
Pricing source (opens in a new tab)

Data & enterprise terms

Fish Audio terms permit Usage Data and Content to improve its models, including third-party components. Public terms do not establish universal zero retention. Free S2.1 has no DPA or TTFA guarantees; confirm production contractual terms separately. Voice inputs require appropriate rights.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro
Access
Production API access; account balance, rate limits and contractual terms apply.
Regions
Processing region and residency not established for this access path.
API endpoint URL
wss://api.fish.audio/v1/tts/liveSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
Streaming text input and audio outputSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M UTF-8 bytes

Rate conditions

  1. Native input text measured in UTF-8 bytes, not Unicode characters or LLM tokens. Pay as you go without a monthly minimum. S1 pricing applies before its scheduled replacement.
Pricing source (opens in a new tab)

Data & enterprise terms

Fish Audio terms permit Usage Data and Content to improve its models, including third-party components. Public terms do not establish universal zero retention. Free S2.1 has no DPA or TTFA guarantees; confirm production contractual terms separately. Voice inputs require appropriate rights.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro
Access
Production API access; account balance, rate limits and contractual terms apply.
Regions
Processing region and residency not established for this access path.
API endpoint URL
wss://api.fish.audio/v1/tts/live/with-timestampSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
Streaming text/audio with timestamp eventsSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M UTF-8 bytes

Rate conditions

  1. Native input text measured in UTF-8 bytes, not Unicode characters or LLM tokens. Pay as you go without a monthly minimum. S1 pricing applies before its scheduled replacement.
Pricing source (opens in a new tab)

Data & enterprise terms

Fish Audio terms permit Usage Data and Content to improve its models, including third-party components. Public terms do not establish universal zero retention. Free S2.1 has no DPA or TTFA guarantees; confirm production contractual terms separately. Voice inputs require appropriate rights.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro-free
Access
Free development tier through November 30, 2026; fair use; no SLA, TTFA or DPA guarantee. Products above $1M ARR must contact the provider.
Regions
Processing region and residency not established for this access path.
API endpoint URL
https://api.fish.audio/v1/ttsSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
Raw audio responseSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)
Usage metering
Free tier scheduled through 2026-11-30; subject to fair useSource for Usage metering (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis · free tier1$0.001M UTF-8 bytes

Rate conditions

  1. Same model as paid S2.1 Pro. Free through November 30, 2026, subject to fair use and commercial restrictions; no production guarantees.
Pricing source (opens in a new tab)

Data & enterprise terms

Requests may be used to improve model quality. No SLA, TTFA or DPA guarantees. Businesses above $1M ARR must contact the provider before use.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro-free
Access
Free development tier through November 30, 2026; fair use; no SLA, TTFA or DPA guarantee. Products above $1M ARR must contact the provider.
Regions
Processing region and residency not established for this access path.
API endpoint URL
https://api.fish.audio/v1/tts/stream/with-timestampSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
SSE audio with word timestampsSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)
Usage metering
Free tier scheduled through 2026-11-30; subject to fair useSource for Usage metering (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis · free tier1$0.001M UTF-8 bytes

Rate conditions

  1. Same model as paid S2.1 Pro. Free through November 30, 2026, subject to fair use and commercial restrictions; no production guarantees.
Pricing source (opens in a new tab)

Data & enterprise terms

Requests may be used to improve model quality. No SLA, TTFA or DPA guarantees. Businesses above $1M ARR must contact the provider before use.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro-free
Access
Free development tier through November 30, 2026; fair use; no SLA, TTFA or DPA guarantee. Products above $1M ARR must contact the provider.
Regions
Processing region and residency not established for this access path.
API endpoint URL
wss://api.fish.audio/v1/tts/liveSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
Streaming text input and audio outputSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)
Usage metering
Free tier scheduled through 2026-11-30; subject to fair useSource for Usage metering (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis · free tier1$0.001M UTF-8 bytes

Rate conditions

  1. Same model as paid S2.1 Pro. Free through November 30, 2026, subject to fair use and commercial restrictions; no production guarantees.
Pricing source (opens in a new tab)

Data & enterprise terms

Requests may be used to improve model quality. No SLA, TTFA or DPA guarantees. Businesses above $1M ARR must contact the provider before use.

Read the service policy (opens in a new tab)
API model ID
s2.1-pro-free
Access
Free development tier through November 30, 2026; fair use; no SLA, TTFA or DPA guarantee. Products above $1M ARR must contact the provider.
Regions
Processing region and residency not established for this access path.
API endpoint URL
wss://api.fish.audio/v1/tts/live/with-timestampSource for API endpoint URL (opens in a new tab)
Request quotas
Shared account concurrency: 5 below $100 total prepaid; 15 from $100; 50 from $1,000; enterprise customSource for Request quotas (opens in a new tab)

Thresholds measure total prepaid funds, not spend. All keys and ASR share the pool; 429 responses have no Retry-After header. Free-tier fair-use conditions also apply.

Request mode
Streaming text/audio with timestamp eventsSource for Request mode (opens in a new tab)
Required request fields
Send the exact model HTTP header. Text plus optional reference_id or inline reference audio; timestamp and WebSocket payloads follow their own contracts.Source for Required request fields (opens in a new tab)
Usage metering
Free tier scheduled through 2026-11-30; subject to fair useSource for Usage metering (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis · free tier1$0.001M UTF-8 bytes

Rate conditions

  1. Same model as paid S2.1 Pro. Free through November 30, 2026, subject to fair use and commercial restrictions; no production guarantees.
Pricing source (opens in a new tab)

Data & enterprise terms

Requests may be used to improve model quality. No SLA, TTFA or DPA guarantees. Businesses above $1M ARR must contact the provider before use.

Read the service policy (opens in a new tab)
API model ID
fish-audio/s2.1-pro
Access
Listed by OpenRouter. Upstream availability, account access and routing policy apply; host listing date is not the native model release date.
Regions
Processing region and residency not established for this access path.
API endpoint URL
https://openrouter.ai/api/v1/audio/speechSource for API endpoint URL (opens in a new tab)
Request mode
Text input to raw audio byte stream, with optional voice and input reference audioSource for Request mode (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M UTF-8 bytes

Rate conditions

  1. OpenRouter published host rate. Rates are not transferred to other hosts.
Pricing source (opens in a new tab)

Data & enterprise terms

OpenRouter prompt/response logging and improvement use are opt-in; metadata is retained. Upstream provider policies remain separate, so routing through OpenRouter does not itself establish Fish Audio zero retention.

Read the service policy (opens in a new tab)
API model ID
fish-audio/s2.1-pro-free:free
Access
Listed by OpenRouter. Upstream availability, account access and routing policy apply; host listing date is not the native model release date.
Regions
Processing region and residency not established for this access path.
API endpoint URL
https://openrouter.ai/api/v1/audio/speechSource for API endpoint URL (opens in a new tab)
Request mode
Text input to raw audio byte stream, with optional voice and input reference audioSource for Request mode (opens in a new tab)

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis · free tier1$0.001M UTF-8 bytes

Rate conditions

  1. OpenRouter published host rate. Free-route fair-use and upstream free-tier conditions apply.
Pricing source (opens in a new tab)

Data & enterprise terms

OpenRouter prompt/response logging and improvement use are opt-in; metadata is retained. Upstream provider policies remain separate, so routing through OpenRouter does not itself establish Fish Audio zero retention.

Read the service policy (opens in a new tab)
API model ID
fish-audio/s2.1-pro
Access
Listed in the public AI Gateway model catalog. Use a supported speech/transcription SDK specification; native HTTP contracts are not presumed identical.
Regions
Processing region and residency not established for this access path.

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M characters

Rate conditions

  1. Uses the catalog’s dedicated speech_input_character_cost field. Generic input fields are not treated as LLM token prices. Native Fish byte units are not substituted for gateway character units.
Pricing source (opens in a new tab)

Data & enterprise terms

The catalog labels this model zdr=none and no_training=none. No zero-retention or no-training guarantee is inferred; confirm host and upstream terms for the intended workload.

Read the service policy (opens in a new tab)
API model ID
fishaudio/s2.1-pro
Access
LiveKit Inference global deployment, billed by LiveKit. A Fish Audio API key is not required.
Regions
Global. The Fish Audio row does not list a dedicated EU endpoint.
Languages
View all 13 entries
  • en
  • zh
  • ja
  • de
  • fr
  • es
  • ko
  • ar
  • ru
  • nl
  • it
  • pl
  • pt
Source for Languages (opens in a new tab)

Host table lists 13 language codes; the native model advertises 83.

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
Speech synthesisSpeech synthesis1$15.001M characters

Rate conditions

  1. Build/Ship and Scale list the same $15 per million characters. LiveKit plans, inference credits and enterprise rates are separate. The host character unit is not replaced by native UTF-8 bytes.
Pricing source (opens in a new tab)

Data & enterprise terms

LiveKit documents zero retention for inference audio/text/model outputs by default, including underlying providers. Optional observability and stored custom voices are separate workflows.

Read the service policy (opens in a new tab)
API model ID
fishaudio/s2.1-pro-free
Access
Historical host selector; retired September 25, 2026. Use the paid LiveKit selector. This does not retire the native free tier.
Regions
Global. The Fish Audio row does not list a dedicated EU endpoint.
Languages
View all 13 entries
  • en
  • zh
  • ja
  • de
  • fr
  • es
  • ko
  • ar
  • ru
  • nl
  • it
  • pl
  • pt
Source for Languages (opens in a new tab)

Host table lists 13 language codes; the native model advertises 83.

Endpoint pricing has not been collected. Check the provider for applicable rates.

Data & enterprise terms

LiveKit documents zero retention for inference audio/text/model outputs by default, including underlying providers. Optional observability and stored custom voices are separate workflows.

Read the service policy (opens in a new tab)

Caching

Caching can reuse earlier input processing. Availability, lifetime and billing depend on the endpoint. A cache hit still generates a new response.

01 / INITIAL INPUTProcess & retain

The system processes eligible input and retains reusable state.

02 / LATER REQUESTCheck available state

Reuse depends on matching input, session state and the cache policy.

03 / CACHE HITReuse & generate

Reusing state can reduce repeated work. Any charges follow the billing rules below.

Fish Audio API

s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro-free
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro-free
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro-free
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Fish Audio API

s2.1-pro-free
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

OpenRouter

fish-audio/s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

OpenRouter

fish-audio/s2.1-pro-free:free
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Vercel AI Gateway

fish-audio/s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

LiveKit Inference

fishaudio/s2.1-pro
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

LiveKit Inference

fishaudio/s2.1-pro-free
Not verified

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How it works
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

How to enable it
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Usage fields
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Billing rules
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract or discount established. Voice references and previous-chunk conditioning are not billed prompt caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

Voice choices

7 voices

Choose a voice within Fish Audio S2.1 Pro. These are API voice identifiers, not additional model releases. Source links document each voice.

Published voice catalog
Voice / API IDLanguage & accentDelivery
Adrianbf322df2096a46f18c579d0baa36f41dEnglish
American
Friendly, casual American male Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)
Ethan536d3a5e000945adb7038665781a4acaEnglish
American
A curious explainer. Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)
Hannah9a9cf47702da476aa4629e2506d4a857English
American
A conversational specialist. Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)
Jordan79d0bd3e4e5444b18f7b6d89b5927bf1English
American
A motivational speaker. Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)
Laurae3cd384158934cc9a01029cd7d278634English
American
A confident female narrator. Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)
Sarah933563129e564b19a115bedd57b7406aEnglish
American
An engaged speaker. Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)
Seleneb347db033a6549378b48d00acb0d06cdEnglish
American
A meditative female voice. Documented LiveKit example, not the complete voice inventory.Voice source (opens in a new tab)

What the measurements say

No benchmark observations have been added for this model. We do not turn a vendor description into a performance score.

Latency and throughput depend on the host, request size, reasoning settings and load. There is no measured speed or global usage figure in this record.

The record behind the model

Why it is included

The official API documents this named managed model under Fish Audio service terms that reserve service IP and restrict reverse engineering. The reviewed official weight inventory does not publish this release; the separately downloadable S2 Pro and S1-mini are excluded. Exact internal checkpoint lineage remains unverified.

Classification evidence (opens in a new tab)

Lifecycle dates

Native model release23 Jun 2026Source (opens in a new tab)

Sources reviewed