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

o3-pro vs Grok 4 Heavy

OpenAI
o3-pro
SpaceXAI
Grok 4 Heavy
Overview
CompanyOpenAISpaceXAI
Release dateJun 10 2025Jul 9 2025
AccessProprietaryProprietary
Timeline
Release gapo3-pro shipped 29 days before Grok 4 Heavy

Which is better: o3-pro or Grok 4 Heavy?

o3-pro and Grok 4 Heavy don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. o3-pro shipped 29 days before Grok 4 Heavy, 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 — o3-pro and Grok 4 Heavy don't publish scores on any of the same benchmarks.

Frequently asked questions

o3-pro was released by OpenAI on Jun 10 2025.

Grok 4 Heavy was released by SpaceXAI on Jul 9 2025.

Other comparisons