ChatGPT Images 2.5 vs GPT-Image-2.5: which name is the API?

They are two names for one model generation. On OpenAI's launch page, ChatGPT Images 2.5 is the product inside ChatGPT, and GPT-Image-2.5 Flare and GPT-Image-2.5 Sunburst are the two API models. If you are writing code against Sume, you call openai/gpt-image-2.5 (Flare) or openai/gpt-image-2.5-sunburst.

Sources: OpenAI's launch page and Sume's Image API docs, both read 2026-09-29.

How do the names map?

The Sume docs call the family "ChatGPT Image 2.5" and list the two ids below. They also say ChatGPT Image 2 remains selectable.

Which ChatGPT features are not in the API?

OpenAI lists Sketch, Templates, comments on images and shared prompts as product features introduced "in ChatGPT". They are described as things you do in the ChatGPT app, and Sume's Image API docs do not list any of them as request fields. What the API takes instead is a prompt, up to 16 reference images, an optional mask_url and a background value.

For the two API models and how to choose, see GPT Image 2.5 Flare vs Sunburst.

What does a call with the API name look like?

Use the Sume id as the model. Everything else is the normal image request.

curl -X POST "https://api.sume.com/v1/images" \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-image-2.5",
    "prompt": "a matte black coffee grinder on a marble counter, soft window light"
  }'

Is the ChatGPT Images name searchable in the Sume catalog?

Read GET /v1/images/models for the live list of ids and their supported parameters. The ids are the source of truth, not the product names, so match on openai/gpt-image-2.5 and openai/gpt-image-2.5-sunburst rather than on any marketing label.

What does OpenAI say about safety on these models?

The launch page says Images 2.5 builds on existing safeguards, with checks on prompts and images, and that OpenAI continues to use C2PA metadata and invisible watermarking to help identify images made with its tools. Sume's docs are silent on that, so treat it as OpenAI's statement about its own tools.

Does the product name change my request?

No. The product name never appears in a request. The model field takes a Sume catalog id. If a teammate says "use ChatGPT Images 2.5", ask which of the two API models they mean: Flare is the one OpenAI calls the default choice for most applications, and OpenAI describes Sunburst as built for premium visual workflows that benefit from tighter control across edits.

Pricing and quality settings depend on the id and on quality, not on the name used in conversation. Prices are on the API pricing page rather than in this post.