GPT Image 2.5

Use one GPT Image 2.5 model ID with the generation or editing endpoint.

Model ID	Recommended use
`gpt-image-2.5-flare`	Default choice for fast, high-quality generation and everyday editing
`gpt-image-2.5-sunburst`	Detailed creative work and edits that require tighter preservation and control

GPT Image 2.5 always returns Base64-encoded image data in data[].b64_json. Do not send the DALL·E-only response_format parameter.

Generate images
Edit images

Generate images

POST /v1/images/generations

cURL

curl --request POST \
  --url https://www.anyfast.ai/v1/images/generations \
  --header 'Authorization: Bearer YOUR_API_KEY' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "gpt-image-2.5-flare",
    "prompt": "A clean editorial product photograph of a translucent green glass bottle on pale stone, soft morning light",
    "size": "1536x1024",
    "quality": "high",
    "background": "opaque",
    "output_format": "jpeg",
    "output_compression": 85,
    "moderation": "auto",
    "n": 1
  }'

Request headers

string

required

Bearer authentication in the form Bearer YOUR_API_KEY.

string

default:"application/json"

required

Data exchange format.

Request body

string

required

Model ID: gpt-image-2.5-sunburst or gpt-image-2.5-flare.

string

required

Text description of the image to generate. Length: 1–32,000 characters.

integer

default:1

Number of images to generate. Supported range: 1–10.

string

default:"auto"

auto or a custom WIDTHxHEIGHT value. Width and height must be multiples of 16, the aspect ratio must be between 1:3 and 3:1, neither edge may exceed 3,840 pixels, and total pixels must be between 655,360 and 8,294,400.

string

default:"auto"

Rendering quality: low, medium, high, xhigh, max, or auto.

string

default:"auto"

Background mode: auto, opaque, or transparent. Transparent backgrounds require PNG or WebP output.

string

default:"png"

Output format: png, jpeg, or webp.

integer

default:100

JPEG or WebP compression level from 0 through 100. Ignored for PNG output.

string

default:"auto"

Moderation strictness: auto or low.

Generation response

200

{
  "created": 1788926400,
  "background": "opaque",
  "data": [
    {
      "b64_json": "iVBORw0KGgoAAA..."
    }
  ],
  "output_format": "jpeg",
  "quality": "high",
  "size": "1536x1024"
}

integer

Creation time as a Unix timestamp in seconds.

string

Resolved background mode: opaque or transparent.

object[]

Generated image results.

string

Base64-encoded image data.

string

Returned image format: png, jpeg, or webp.

string

Quality level used for the result.

string

Resolved output dimensions as WIDTHxHEIGHT.

Edit images

POST /v1/images/edits

cURL

curl --request POST \
  --url https://www.anyfast.ai/v1/images/edits \
  --header 'Authorization: Bearer YOUR_API_KEY' \
  --form 'model=gpt-image-2.5-sunburst' \
  --form 'image[]=@/path/to/product.png' \
  --form 'mask=@/path/to/mask.png' \
  --form 'prompt=Keep the product unchanged and replace the background with a warm studio gradient' \
  --form 'size=1536x1024' \
  --form 'quality=xhigh' \
  --form 'background=opaque' \
  --form 'output_format=png' \
  --form 'n=1'

Request headers

string

required

Bearer authentication in the form Bearer YOUR_API_KEY.

string

default:"multipart/form-data"

required

Set automatically when using multipart form uploads.

Request body

string

required

Model ID: gpt-image-2.5-sunburst or gpt-image-2.5-flare.

file

One source image file. Use image[] instead when uploading multiple images. Each source image must be smaller than 50 MB.

file[]

Up to 16 source image files. Do not send both image and image[].

file

Optional edit mask. It guides the edit rather than defining a guaranteed pixel-exact boundary. It must contain an alpha channel, match the first source image’s format and dimensions, and be smaller than 50 MB. With multiple source images, the mask applies to the first image.

string

required

Instructions describing the edit. Length: 1–32,000 characters.

integer

default:1

Number of edited images to return. Supported range: 1–10.

string

default:"auto"

auto or a valid custom WIDTHxHEIGHT value using the same limits as image generation.

string

default:"auto"

Rendering quality: low, medium, high, xhigh, max, or auto.

string

default:"auto"

Background mode: auto, opaque, or transparent. Transparent backgrounds require PNG or WebP output.

string

default:"png"

Output format: png, jpeg, or webp.

integer

default:100

JPEG or WebP compression level from 0 through 100. Ignored for PNG output.

string

default:"auto"

Moderation strictness: auto or low.

Edit response

200

{
  "created": 1788926460,
  "background": "opaque",
  "data": [
    {
      "b64_json": "iVBORw0KGgoAAA..."
    }
  ],
  "output_format": "png",
  "quality": "xhigh",
  "size": "1536x1024"
}

integer

Creation time as a Unix timestamp in seconds.

string

Resolved background mode: opaque or transparent.

object[]

Edited image results.

string

Base64-encoded edited image data.

string

Returned image format: png, jpeg, or webp.

string

Quality level used for the result.

string

Resolved output dimensions as WIDTHxHEIGHT.

Validation rules

background="transparent" requires output_format="png" or output_format="webp".
Custom width and height must be divisible by 16, use an aspect ratio from 1:3 through 3:1, keep each edge at or below 3,840 pixels, and contain 655,360–8,294,400 total pixels.
Resolutions above 2560x1440 are experimental.
output_compression applies only to JPEG and WebP output.
GPT Image 2.5 returns Base64 image data; URL output through response_format is not supported.

See the OpenAI create image reference and create image edit reference for the upstream contract.

Overview

Native Compatible Endpoints

Model APIs

Generate images

Request headers

Request body

Generation response

Edit images

Request headers

Request body

Edit response

Validation rules

​Generate images

​Request headers

​Request body

​Generation response

​Edit images

​Request headers

​Request body

​Edit response

​Validation rules

Generate images

Request headers

Request body

Generation response

Edit images

Request headers

Request body

Edit response

Validation rules