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Model infoModelsSnapshot: 15 Oct 2026

Stability AI / Stable Image managed services

Fast Upscaler

Lightweight image enlargement without a text-prompt field.

Image generation
availableClosed weightsImage upscaling
Official documentation (opens in a new tab)Reviewed 13 Oct 2026
7 of 21 specification fields collected
Output resolutionUp to 4 megapixelsSee specification notes below
Output formatsJPEG, PNG, WEBPSee specification notes below
Input billingSee ratesStability AI 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
ImageSource for Input modalities (opens in a new tab)
Output modalities
ImageSource for Output modalities (opens in a new tab)
Reasoning
Not collected
Tool calling
Not collected
Structured output
Not collected
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
Not collected
Output formats
JPEG, PNG, WEBPSource for Output formats (opens in a new tab)
Input file formats
JPEG, PNG, WEBPSource for Input file formats (opens in a new tab)
Image input limits
Width and height: 32–1,536 px; 1,024–1,048,576 total pixelsSource for Image input limits (opens in a new tab)

Bounds apply to the principal source image; masks and auxiliary references have their own fields.

Output resolutions
Up to 4 megapixelsSource for Output resolutions (opens in a new tab)
Upscale factors
4× as described by the providerSource for Upscale factors (opens in a new tab)

The provider’s 4× wording is retained without inferring a separate width/height multiplier.

Access & pricing

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

Stability AI API

Provider source (opens in a new tab)
API model ID
Not collected

No pinned model selector established for this access path.

Access
Developer account, API key and credits required. Public documentation and contracts reviewed; no inference request was made.
Regions
Not established for this endpoint; account availability is not a data-residency guarantee.
API endpoint URL
POST https://api.stability.ai/v2beta/stable-image/upscale/fastSource for API endpoint URL (opens in a new tab)
Request mode
Returns the completed media in the responseSource for Request mode (opens in a new tab)

JSON or base64 transport does not establish structured model output, streaming or a batch API.

Required request fields
imageSource for Required request fields (opens in a new tab)
Output formats
JPEG, PNG, WEBPSource for Output formats (opens in a new tab)
Input modalities
ImageSource for Input modalities (opens in a new tab)
Output modalities
ImageSource for Output modalities (opens in a new tab)
Input file formats
JPEG, PNG, WEBPSource for Input file formats (opens in a new tab)
Image input limits
Width and height: 32–1,536 px; 1,024–1,048,576 total pixelsSource for Image input limits (opens in a new tab)

Bounds apply to the principal source image; masks and auxiliary references have their own fields.

Prices retain their published currencies and billing units below.

Published billing units · original currency · observed 13 Oct 2026
CategoryUsageRateUnit
ImageFast Upscaler1$0.02successful generation

Rate conditions

  1. 2 credits × published $0.01/credit. Direct API flat rate; failed generations are not charged. No text-token or per-question conversion.
Pricing source (opens in a new tab)

Data & enterprise terms

Stability terms permit using content to improve services and describe a training opt-out. This is not a default no-training or zero-retention guarantee. Partner contracts may differ; enterprise terms must be verified separately.

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.

Stability AI API

Not verified
How it works
Not collected
Minimum reusable input
Not collected
Lifetime & refresh
Not collected
How to enable it
Not collected
Usage fields
Not collected
Billing rules
Not collected
Limits & data boundaries
Not collected

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

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

This record identifies a proprietary hosted release or an explicitly labeled managed service under Stability’s service terms, which prohibit reverse engineering. It does not reclassify publicly downloadable Stable Diffusion base weights as closed. Service-specific fine-tunes and orchestration are not distributed as the corresponding base-model weight release; exact internal checkpoint lineage remains unverified.

Classification evidence (opens in a new tab)

Sources reviewed