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OpenAI

GPT Image 2.5 Sunburst

Save 70%Official

openai/gpt-image-2.5-sunburst

OpenAI GPT Image 2.5 Sunburst — the precision tier of the 2.5 family for demanding editing and creative work, billed per image.

Input modalities
text · image
Output modalities
image
Capabilities
Image generation · Image editing
Upstream release
2026-09-08
RouteMux name
openai/gpt-image-2.5-sunburst
Live model playground

Try GPT Image 2.5 Sunburst here

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2Live result

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image

What is GPT Image 2.5 Sunburst

GPT Image 2.5 Sunburst is one of the two image models OpenAI released on 8 September 2026. Sunburst is the precision one: it holds fine detail, and it drifts less when you edit the same image several times in a row. That matters for posters, product shots and brand assets, where the third edit should not quietly redraw something you were happy with.

It is slower per image than GPT Image 2.5 Flare, which is the trade you are making. Flare is the faster default; reach for Sunburst when the output is going somewhere that will be looked at closely. They are separate model ids, not two quality settings of one model, so you choose between them by name rather than by parameter.

Billing is per image, not per token. One image costs one fixed amount — however long your prompt is, however complex the scene. Budgeting is price times image count, with no test batch needed to find out what an image will cost.

Each call returns one image. The size parameter selects the aspect ratio rather than the resolution, and the dimensions that come back are the ones that count. The response follows the OpenAI Images shape, with the image itself returned as base64 in data[0].b64_json.

It speaks the OpenAI Images protocol, so /v1/images/generations and /v1/images/edits take the same request shape as calling OpenAI directly.

GPT Image 2.5 Sunburst API pricing

Source: relay_per_call_2026_09 · Verified 2026-09-10

OutputOfficial $0.062 /call
$0.0186/callSave 70%

Cache read $0.6/M · Cache write /M

Estimate cost

Estimated cost$0.015

Limited time20% extra Credits on your first top-up — up to 200 bonus Credits

Applies to your first top-up within 72 hours of signing up. Minimum $20, once per account.

Sign up and claimNo subscription. Pay for what you use.

Key capabilities

The precision tier

Built for edit fidelity and fine detail rather than speed. Slower per image than Flare.

Steadier across edits

Repeated edits to the same image are less likely to disturb the parts you did not ask to change.

Flat price per image

One price per image, independent of prompt length or scene complexity. Budget is price times count.

Native OpenAI Images

Same request shape as calling OpenAI directly — existing code mostly works unchanged.

Interface and protocols

OpenAI Images

Use any of these IDs to call this model via the API.

RouteMux nameopenai/gpt-image-2.5-sunburst

Replace the ROUTEMUX_KEY placeholder with your API key. Create one →

from openai import OpenAI

client = OpenAI(
    base_url="https://api.routemux.com/v1",
    api_key="<ROUTEMUX_KEY>",
)

response = client.images.generate(
    model="openai/gpt-image-2.5-sunburst",
    prompt="A red panda coding under the moonlight",
    n=1,
)
print(response.data[0].url)
base_url: https://api.routemux.com/v1

Performance (last 30 days)

GPT Image 2.5 Sunburst FAQ

What is GPT Image 2.5 Sunburst?

OpenAI GPT Image 2.5 Sunburst — the precision tier of the 2.5 family for demanding editing and creative work, billed per image.

How much does the GPT Image 2.5 Sunburst API cost?

Through RouteMux, GPT Image 2.5 Sunburst is priced at $0.0186, below the official list price.

How do I call GPT Image 2.5 Sunburst via API?

GPT Image 2.5 Sunburst is OpenAI-compatible: point your base URL at RouteMux and set the model field to openai/gpt-image-2.5-sunburst — no code changes needed.

Which input and output modalities does GPT Image 2.5 Sunburst support?

GPT Image 2.5 Sunburst accepts text, image as input and produces image as output.

When was GPT Image 2.5 Sunburst released?

GPT Image 2.5 Sunburst was released on September 8, 2026.

Is it billed per image?

Yes. A flat price per image, not per token. Prompt length and image content do not change what you pay.

How does it differ from GPT Image 2.5 Flare?

Sunburst is built for edit precision and takes longer per image; Flare is the faster default. They are two separate model ids from OpenAI, priced the same here.

Do I get image data or a URL?

Image data. The image comes back as base64 in data[0].b64_json, in the standard OpenAI Images response shape.

Can it edit an existing image?

Yes — through /v1/images/edits, which accepts reference images as input. This is the model in the pair built for that job.

Sources