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Model infoModelsSnapshot: 15 Oct 2026

ByteDance / Seed

Seed 1.6 Flash (250615)

Seed 1.6 Flash language-model revision 250615, with documented reasoning and tool calling through ModelArk.

Language models (LLMs)
deprecatedClosed weightsText generation
Official documentation (opens in a new tab)Reviewed 15 Oct 2026
11 of 19 specification fields collected
Input token limit224KSee specification notes below
Maximum output32KSee specification notes below
Input billingNot collectedBytePlus ModelArk
Output billingNot collectedNo inferred price

Specifications

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

Context / input limit
256KSource for Context / input limit (opens in a new tab)

Provider K-token notation retained. Output limit includes chain-of-thought tokens.

Maximum output
32KSource for Maximum output (opens in a new tab)

Provider K-token notation retained. Output limit includes chain-of-thought tokens.

Input modalities
Text, Image, VideoSource for Input modalities (opens in a new tab)
Output modalities
TextSource for Output modalities (opens in a new tab)
Reasoning
SupportedSource for Reasoning (opens in a new tab)
Tool calling
SupportedSource for Tool calling (opens in a new tab)
Structured output
SupportedSource for Structured output (opens in a new tab)

The catalog labels structured output beta. JSON schema is explicitly recommended for the April 2026 Mini and Lite releases.

Streaming
Not collected
Batch processing
Not collected
Fine-tuning
Not collected
Knowledge cutoff
Not collected
Release date
Not collected
Parameters
Not collected
Architecture
Not collected
Languages
Not collected
Context caching
SupportedSource for Context caching (opens in a new tab)
Maximum input tokens
224KSource for Maximum input tokens (opens in a new tab)

Provider K-token notation retained. Output limit includes chain-of-thought tokens.

Maximum thinking tokens
32KSource for Maximum thinking tokens (opens in a new tab)

Provider K-token notation retained. Output limit includes chain-of-thought tokens.

Published request quota
15K Max RPM; 800K Max TPMSource for Published request quota (opens in a new tab)

Published quota, not a throughput or latency benchmark.

Access & pricing

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

BytePlus ModelArk · standard

Provider source (opens in a new tab)
API model ID
seed-1-6-flash-250615
Access
Deprecated: new endpoint creation ended September 15, 2026. Existing service is scheduled to stop November 11, 2026.
Regions
Not collected
Service tier
standardSource for Service tier (opens in a new tab)
Endpoint availability
Deprecated: new endpoint creation ended September 15, 2026. Existing service is scheduled to stop November 11, 2026.Source for Endpoint availability (opens in a new tab)

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

Data & enterprise terms

Retention, training use, regional processing and enterprise terms have not been summarized for this endpoint.

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.

BytePlus ModelArk · standard

seed-1-6-flash-250615
Documented
Support evidence (opens in a new tab)
How it works
Implicit: Batch API (Chat), Batch Inference API (Job). Explicit: Responses API, Prefix caching, Session caching.Source for How it works (opens in a new tab)
Minimum reusable input
Implicit: 1,024 tokens. Explicit prefix: 256 tokens. Session cache has no minimum stated.Source for Minimum reusable input (opens in a new tab)
Lifetime & refresh
Implicit retention is dynamic. Responses explicit caching expires at expire_at, at most 7 days after creation; reuse does not extend expiration.Source for Lifetime & refresh (opens in a new tab)
How to enable it
Implicit caching is automatic. Responses explicit caching requires store=true and caching.type=enabled; reuse the stored response/prefix identifier.Source for How to enable it (opens in a new tab)
Usage fields
Inspect cached_tokens in the response usage details to distinguish hits from uncached input.Source for Usage fields (opens in a new tab)
Billing rules
Cached-input rates depend on prompt length. Implicit storage is free. Explicit storage is billed separately, rounded to natural hours.Source for Billing rules (opens in a new tab)
Limits & data boundaries
Explicit caching replaces implicit caching for that request. The older Context API uses a different, sliding TTL; its default is not copied to Responses caching.Source for Limits & data boundaries (opens in a new tab)

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

Caching reviewed 12 Oct 2026

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

Inferred from the named native hosted API offering and cross-check of ByteDance and ByteDance-Seed public repositories. No matching downloadable checkpoint was found. This is not an explicit published weight-license declaration.

Classification evidence (opens in a new tab)

Lifecycle dates

BytePlus deprecation announced8 Sept 2026Source (opens in a new tab)
BytePlus new endpoint creation ended15 Sept 2026Source (opens in a new tab)
BytePlus service shutdown scheduled11 Nov 2026Source (opens in a new tab)

Sources reviewed