Composer 1.5vsComposer 2

Composer 1.5
Composer 2
Benchmarks
Next.js Evals
67%58%
Benchmarks
SWE-Bench Multilingual
73.7%
Terminal-Bench 2.0
61.7%
Overview
CompanySpaceXAISpaceXAI
Release dateFeb 9 2026Mar 19 2026
AccessProprietaryProprietary

Other comparisons

Composer 1.5vsClaude Fable 5.1Composer 2vsClaude Fable 5.1Composer 1.5vsGPT-6 AstraComposer 2vsGPT-6 AstraComposer 1.5vsGemini 3.8 FlashComposer 2vsGemini 3.8 FlashComposer 1.5vsMuse Spark 1.3Composer 2vsMuse Spark 1.3Composer 1.5vsDeepSeek-V4.1-FlashComposer 2vsDeepSeek-V4.1-FlashComposer 1.5vsMistral Medium 3.5Composer 2vsMistral Medium 3.5

Frequently asked questions

Composer 1.5 leads Composer 2 on 1 of the 1 benchmark they both report (Next.js Evals). Composer 1.5 shipped 38 days before Composer 2, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

On Next.js Evals, Composer 1.5 leads at 67% vs Composer 2 at 58%.