GPT Image 2 / 2.5 Image Generation API

¶ 1. Get an API Key

Open the WorldAi application list, enter an available application, and copy the API Key.

¶ 2. Send the First Request

curl https://api.worldai.chat/openai/images/generations \
  -H "Authorization: Bearer 你的 API Key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-image-2",
    "prompt": "Minimal editorial product illustration: one plain white ceramic coffee mug centered on a solid cobalt blue tabletop, pale cream background, soft shadow, clean geometric shapes, no text, no logo, portrait composition",
    "size": "1024x1536"
  }'

The image in a successful response is located at data[].url. Below is the actual 1024×1536 result obtained through a request via WorldAi on September 8, 2026 (task d56455e2-e7f7-4bcd-b935-475b0a1e0948, trace eb938601-8192-407f-b539-1e0554b697ec):

¶ 3. Common Parameters

Field	Description
model	gpt-image-2 (recommended by default), gpt-image-2.5-flare (faster), or gpt-image-2.5-sunburst (higher fidelity and control); all three can use their corresponding :official variants, while gpt-image-2 also supports :reverse
prompt	Image description, up to 32,000 characters
size	auto or WIDTHxHEIGHT; width and height must be multiples of 16, the longest side must not exceed 3840, total pixels must be 655,360–8,294,400, and the aspect ratio must not exceed 3:1
n	1–10; only 1 is supported when response_format=b64_json
quality	GPT Image models support auto, low, medium, and high; only 2.5 Flare / Sunburst (including :official) additionally support xhigh and max. Official channels are billed based on actual Token usage
response_format	url or b64_json
callback_url	Optional; sends results to this address after a long-running task is completed

Common sizes:

Ratio	1K	2K	4K
1:1	1024x1024	2048x2048	2880x2880
4:3	1536x1024	2048x1536	3264x2448
3:4	1024x1536	1536x2048	2448x3264
16:9	1792x1024	2048x1152	3840x2160
9:16	1024x1792	1152x2048	2160x3840

size: "auto" selects the canvas based on the ratio, pixels, and layout intent in the prompt; directly specify the dimensions when precise pixels are required.

¶ Models and Billing Methods

Model	Applicable Scenarios and Billing Methods
gpt-image-2	Default reverse channel, fixed billing per successfully generated image
gpt-image-2:reverse	Explicitly selects the reverse channel, fixed billing per successfully generated image
gpt-image-2:official	Official API channel, higher stability, billed based on actual Token usage
gpt-image-2.5-flare	Focuses on generation speed, fixed billing per successfully generated image
gpt-image-2.5-flare:official	Official API channel, higher stability and focuses on generation speed, billed based on actual Token usage
gpt-image-2.5-sunburst	Focuses on high fidelity and fine-grained control, fixed billing per successfully generated image
gpt-image-2.5-sunburst:official	Official API channel, higher stability and focuses on high fidelity and fine-grained control, billed based on actual Token usage

The listed prices for official API channels are estimates before the request; the final amount is based on the actual Token usage in the response and usage records.

¶ 4. Multiple Image Generation

curl https://api.worldai.chat/openai/images/generations \
  -H "Authorization: Bearer 你的 API Key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-image-2",
    "prompt": "A small fox reading under a glowing mushroom, watercolor illustration",
    "size": "1536x1024",
    "n": 2
  }'

gpt-image-2, gpt-image-2.5-flare, gpt-image-2.5-sunburst, and gpt-image-2:reverse are billed per successfully generated image; gpt-image-2:official, gpt-image-2.5-flare:official, and gpt-image-2.5-sunburst:official are billed based on the actual text input and image output Tokens in the response. The listed prices are estimates before the request, and the final amount is based on usage records.

¶ 5. Asynchronous Callbacks

After adding callback_url to the request body, the API first returns {"task_id": "..."} and POSTs the final result to that URL upon completion; synchronous requests still return created and data:

{
  "model": "gpt-image-2",
  "prompt": "A product poster with clear typography",
  "size": "1024x1024",
  "callback_url": "https://example.com/webhooks/images"
}

The callback receiver should use task_id for deduplication and verify the request source and data format.

¶ 6. Troubleshooting

Status	Check
400	Combination of model, prompt, size format, n, and response_format
401	Whether the API Key is complete and whether the Header is Authorization: Bearer ...
429	Requests are too frequent; retry later
504	Synchronous generation timed out; use callback_url instead

Error responses include error.code, error.message, and trace_id. When reporting an issue, provide the trace_id; do not provide the API Key.

For complete fields and real-time enumerations, refer to the OpenAI Images Generations API page. For image editing, see GPT Image 2 / 2.5 Image Editing.