AI Model Release Tracker - Timeline of Major AI Models from 2022-2026

AI Model Release Tracker

Mistral Medium 3.5 vs Kimi K2 Thinking

Mistral
Mistral Medium 3.5
Moonshot AI
Kimi K2 Thinking
Overview
CompanyMistralMoonshot AI
Release dateApr 29 2026Nov 6 2025
Model type——
Open sourceYesYes
Specifications
Parameters
128B
1T
Context window
256k
256k
Benchmarks
Coding
SWE-Bench Verified
77.6%Best
71.3%
Timeline
Release gapKimi K2 Thinking shipped 174 days before Mistral Medium 3.5

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

When was Mistral Medium 3.5 released?
Mistral Medium 3.5 was released by Mistral on Apr 29 2026.
When was Kimi K2 Thinking released?
Kimi K2 Thinking was released by Moonshot AI on Nov 6 2025.
Which is better at coding, Mistral Medium 3.5 or Kimi K2 Thinking?
Mistral Medium 3.5 leads on SWE-Bench Verified — Mistral Medium 3.5 77.6% vs Kimi K2 Thinking 71.3%.
How do the context windows of Mistral Medium 3.5 and Kimi K2 Thinking compare?
Mistral Medium 3.5 has a 256k context window; Kimi K2 Thinking has 256k.

Other comparisons

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