GPT-Image-2 ｜ Text To Image

Authentication

Sign up for a GPTProto account at https://gptproto.com
Navigate to the API Keys section in your dashboard
Generate a new API key (sk-xxxxx)
Copy and securely store your API key For authentication details, please refer to the Authentication section.

Initiate Request

curl --location 'https://gptproto.com/api/v3/openai/gpt-image-2/text-to-image' \
--header 'Authorization: GPTPROTO_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
  "prompt": "Girl holding cat",
  "quality": "medium",
  "size": "1024x1024",
  "background": "auto",
  "enable_sync_mode": false,
  "response_format": "url"
}'

Query Result

If the request that generated your content includes the parameter enable_sync_mode set to true (some models do not support this parameter, but you still need to query the result by id), you must call the Query Result endpoint to retrieve the final output.

curl -X GET "https://gptproto.com/api/v3/predictions/{id}/result" \
  -H "Authorization: GPTPROTO_API_KEY" \
  -H "Content-Type: application/json"

After submitting your prediction request, the response will contain the id you need.
You can find it in either:

data.id – the unique identifier of the prediction
data.urls[0].get – a ready-to-use GET URL that already embeds the id

Response Example

{
    "data": {
        "id": "abc",
        "model": "model_name",
        "outputs": [],
        "urls": {
            "get": "https://gptproto.com/api/v3/predictions/abc/result"
        },
        "status": "completed",
        "error": null,
        "executionTime": 0,
        "timings": {
            "inference": 0
        },
        "has_nsfw_contents": [],
        "created_at": "2026-01-01 00:00:00"
    },
    "message": "success",
    "code": 200
}

Parameters

Text to Image
Image Edit

Core Parameters

Parameter	Type	Required	Default	Range	Description
`prompt`	string	✅ Yes	-	1–32000 chars	A text description of the desired image(s). The maximum length is 32000 characters.
`n`	integer	❌ No	`1`	`1-10`	The number of images to generate. Must be between 1 and 10.
`size`	string	❌ No	`1024x1024`	`1024x1024` `1536x1024` `1024x1536` `2048x2048` `2048x1152` `3840x2160` `2160x3840` or any valid custom size	The size of the generated images. For gpt-image-1: one of 1024x1024, 1536x1024, or 1024x1536. For gpt-image-2: supports arbitrary resolutions (max edge ≤ 3840px, both sides must be multiples of 16px, aspect ratio ≤ 3:1, total pixels between 655,360 and 8,294,400).
`quality`	string	❌ No	`auto`	`auto` `high` `medium` `low`	The quality of the generated images. One of auto, low, medium, or high. Defaults to auto. Not supported by `-plus` suffixed models.
`enable_sync_mode`	boolean	❌ No	`false`	`true` `false`	Whether to enable synchronous mode for image generation. When enabled, the API will wait until the image is fully generated before returning the response.
`response_format`	string	❌ No	`url`	`url` `b64_json`	The format in which the generated images are returned. `url` returns a temporary URL, `b64_json` returns base64-encoded JSON.

Core Parameters

Parameter	Type	Required	Default	Range	Description
`prompt`	string	✅ Yes	-	1–32000 chars	A text description of the desired image edit. The maximum length is 32000 characters.
`base64_images`	array of string	⚠️ Conditional	-	-	A list of base64-encoded input images. Each entry should be a data URI (e.g. `data:image/png;base64,...`). At least one of `base64_images` or `images` is required.
`images`	array of string	⚠️ Conditional	-	-	A list of image URLs to use as input for editing. At least one of `base64_images` or `images` is required. Both can be provided simultaneously.
`n`	integer	❌ No	`1`	`1-10`	The number of images to generate. Must be between 1 and 10.
`size`	string	❌ No	`1024x1024`	`1024x1024` `1536x1024` `1024x1536` `2048x2048` `2048x1152` `3840x2160` `2160x3840` or any valid custom size	The size of the generated images. For gpt-image-1: one of 1024x1024, 1536x1024, or 1024x1536. For gpt-image-2: supports arbitrary resolutions (max edge ≤ 3840px, both sides must be multiples of 16px, aspect ratio ≤ 3:1, total pixels between 655,360 and 8,294,400).
`quality`	string	❌ No	`auto`	`auto` `high` `medium` `low`	The quality of the generated images. One of auto, low, medium, or high. Defaults to auto. Not supported by `-plus` suffixed models.
`enable_sync_mode`	boolean	❌ No	`false`	`true` `false`	Whether to enable synchronous mode for image generation. When enabled, the API will wait until the image is fully generated before returning the response.
`response_format`	string	❌ No	`url`	`url` `b64_json`	The format in which the generated images are returned. `url` returns a temporary URL, `b64_json` returns base64-encoded JSON.

Error Codes

Common Error Codes

Error Code	Error Name	Description
401	Unauthorized	API key is missing or invalid
403	Forbidden	Your API key doesn’t have permission to access this resource, or insufficient balance for the requested operation
429	Too Many Requests	You’ve exceeded your rate limit
500	Internal server error	An internal server error occurred
503	Content policy violation	Content blocked due to safety concerns (actual status code is 400)

API Reference

​Authentication

​Initiate Request

​Query Result

​Parameters

​Core Parameters

​Core Parameters

​Error Codes

​Common Error Codes

Authentication

Initiate Request

Query Result

Parameters

Core Parameters

Core Parameters

Error Codes

Common Error Codes