What is the difference between GPT Image 2.5 Flare and Stable Diffusion 3.5 Medium?

GPT Image 2.5 Flare is developed by OpenAI while Stable Diffusion 3.5 Medium is developed by Stability AI. You can compare their actual outputs across 17 challenges on Rival to see how they differ in practice.

Which is better, GPT Image 2.5 Flare or Stable Diffusion 3.5 Medium?

It depends on your use case. GPT Image 2.5 Flare and Stable Diffusion 3.5 Medium each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 17 challenges so you can judge which fits your needs best.

How can I compare GPT Image 2.5 Flare and Stable Diffusion 3.5 Medium on Rival?

This page shows a side-by-side comparison of GPT Image 2.5 Flare and Stable Diffusion 3.5 Medium across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Sep 2026

GPT Image 2.5 FlarevsStable Diffusion 3.5 Medium

GPT Image 2.5 Flare is the newer model, released after Stable Diffusion 3.5 Medium.

GPT Image 2.5 Flare and Stable Diffusion 3.5 Medium compared across 17 shared prompts
Spec	GPT Image 2.5 Flare	Stable Diffusion 3.5 Medium
Input price	$5/M tokens	—
Output price	$30/M tokens	—
Parameters	Not disclosed	Not disclosed
Weights	Closed	Open
Free API (OpenRouter)	No	—
Released	Sep 2026	Oct 2024