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

Mistral NeMo vs GPT-5.5-Pro

Mistral
Mistral NeMo
OpenAI
GPT-5.5-Pro
Overview
CompanyMistralOpenAI
Release dateJul 18 2024Apr 23 2026
AccessOpen WeightProprietary
Specifications
Parameters
12B
Context window
128k
Benchmarks
Nonsense detection
BullshitBench v2
36%
Next.js coding
Next.js Evals
83%
Web browsing
BrowseComp
90.1%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
57.2%
Advanced math
FrontierMath · Tier 1–3
52.4%
Advanced math
FrontierMath · Tier 4
39.6%
Knowledge work
GDPval (win/tie rate)
82.3%
Timeline
Release gapMistral NeMo shipped 644 days before GPT-5.5-Pro

Which is better: Mistral NeMo or GPT-5.5-Pro?

Mistral NeMo and GPT-5.5-Pro don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Mistral NeMo shipped 644 days before GPT-5.5-Pro, so benchmark comparisons should account for the intervening progress.

Mistral NeMo is open weight, while GPT-5.5-Pro is proprietary.

Direct benchmark comparisons are unavailable — Mistral NeMo and GPT-5.5-Pro don't publish scores on any of the same benchmarks.

Frequently asked questions

Mistral NeMo was released by Mistral on Jul 18 2024.

GPT-5.5-Pro was released by OpenAI on Apr 23 2026.

Mistral NeMo is an open weight model released by Mistral. GPT-5.5-Pro is a proprietary model released by OpenAI.

Other comparisons