What is the difference between GPT-5.1-Codex-Mini and Muse Spark 1.3?

GPT-5.1-Codex-Mini is developed by OpenAI while Muse Spark 1.3 is developed by Meta AI. GPT-5.1-Codex-Mini has a 400K token context window vs Muse Spark 1.3's 1.0M. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.

Which is better, GPT-5.1-Codex-Mini or Muse Spark 1.3?

It depends on your use case. GPT-5.1-Codex-Mini and Muse Spark 1.3 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 54 challenges so you can judge which fits your needs best.

How much does GPT-5.1-Codex-Mini cost compared to Muse Spark 1.3?

GPT-5.1-Codex-Mini costs $1.5/M input tokens and Muse Spark 1.3 costs $1.25/M input tokens. Muse Spark 1.3 is $0.25/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare GPT-5.1-Codex-Mini and Muse Spark 1.3 on Rival?

This page shows a side-by-side comparison of GPT-5.1-Codex-Mini and Muse Spark 1.3 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-5.1-Codex-MinivsMuse Spark 1.3

Muse Spark 1.3 is cheaper than GPT-5.1-Codex-Mini at $1.25/M vs $1.5/M input tokens.

GPT-5.1-Codex-Mini and Muse Spark 1.3 compared across 54 shared prompts
Spec	GPT-5.1-Codex-Mini	Muse Spark 1.3
Input price	$1.5/M tokens	$1.25/M tokens
Output price	$6/M tokens	$4.25/M tokens
Context window	400K tokens	1.0M tokens
Weights	Closed	Closed
Free API (OpenRouter)	No	No
Released	Nov 2025	Sep 2026