Mistral Medium 3.5vsKimi K2 Thinking
Mistral Medium 3.5 | Kimi K2 Thinking | |
|---|---|---|
| Specifications | ||
Parameters | 128B | 1T |
Context window | 256k | 256k |
| Benchmarks | ||
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | 77.6%Best | 71.3% |
Community preference (code) Arena Elo (Code)Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | 1267 | — |
| Overview | ||
| Company | Mistral | Moonshot AI |
| Release date | Apr 29 2026 | Nov 6 2025 |
| Access | Open Weight | Open Weight |
Which is better: Mistral Medium 3.5 or Kimi K2 Thinking?
Mistral Medium 3.5 leads Kimi K2 Thinking on 1 of the 1 benchmark they both report (SWE-Bench Verified). Kimi K2 Thinking shipped 174 days before Mistral Medium 3.5, so benchmark comparisons should account for the intervening progress.
Mistral Medium 3.5 has 128B parameters, while Kimi K2 Thinking has 1T. Context windows are 256k (Mistral Medium 3.5) vs 256k (Kimi K2 Thinking).
On SWE-Bench Verified, Mistral Medium 3.5 leads at 77.6% vs Kimi K2 Thinking at 71.3%.
Frequently asked questions
Mistral Medium 3.5 was released by Mistral on Apr 29 2026.
Kimi K2 Thinking was released by Moonshot AI on Nov 6 2025.
Mistral Medium 3.5 leads on SWE-Bench Verified — Mistral Medium 3.5 77.6% vs Kimi K2 Thinking 71.3%.
Mistral Medium 3.5 has a 256k context window; Kimi K2 Thinking has 256k.