Mistral Medium 3.5vsComposer 2.5

Mistral Medium 3.5
Composer 2.5
Specifications
Parameters
128B
Context window
256k
Benchmarks
Agentic coding
SWE-Bench Pro
54%
Coding
SWE-Bench Verified
77.6%
Multilingual coding
SWE-Bench Multilingual
79.8%
Agentic coding
CursorBench v3.2
56.1%
Agentic coding
CursorBench v3.1
63.2%
Agentic coding
DeepSWE 1.0
18%
Next.js coding
Next.js Evals
92%
Agentic terminal coding
Terminal-Bench 2.1
73%
Agentic terminal coding
Terminal-Bench 2.0
69.3%
Community preference (code)
Arena Elo (Code)
1267
Overview
CompanyMistralSpaceXAI
Release dateApr 29 2026May 18 2026
AccessOpen WeightProprietary

Which is better: Mistral Medium 3.5 or Composer 2.5?

Mistral Medium 3.5 and Composer 2.5 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Mistral Medium 3.5 shipped 19 days before Composer 2.5, so benchmark comparisons should account for the intervening progress.

Mistral Medium 3.5 is open weight, while Composer 2.5 is proprietary.

Direct benchmark comparisons are unavailable — Mistral Medium 3.5 and Composer 2.5 don't publish scores on any of the same benchmarks.

Frequently asked questions

Mistral Medium 3.5 was released by Mistral on Apr 29 2026.

Composer 2.5 was released by SpaceXAI on May 18 2026.

Mistral Medium 3.5 is an open weight model released by Mistral. Composer 2.5 is a proprietary model released by SpaceXAI.

Other comparisons