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

Mistral Medium 3.5 vs gpt-oss-20b

Mistral
Mistral Medium 3.5
OpenAI
gpt-oss-20b
Overview
CompanyMistralOpenAI
Release dateApr 29 2026Aug 5 2025
Model type
Open sourceYesYes
Specifications
Parameters
128B
Context window
256k
Benchmarks
Coding
SWE-Bench Verified
77.6%
Timeline
Release gapgpt-oss-20b shipped 267 days before Mistral Medium 3.5

Which is better: Mistral Medium 3.5 or gpt-oss-20b?

Mistral Medium 3.5 and gpt-oss-20b don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. gpt-oss-20b shipped 267 days before Mistral Medium 3.5, 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.

Direct benchmark comparisons are unavailable — Mistral Medium 3.5 and gpt-oss-20b don't publish scores on any of the same benchmarks.

Frequently asked questions

When was Mistral Medium 3.5 released?
Mistral Medium 3.5 was released by Mistral on Apr 29 2026.
When was gpt-oss-20b released?
gpt-oss-20b was released by OpenAI on Aug 5 2025.

Other comparisons