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

GPT-4.5 vs Grok 4.20 Beta

OpenAI
GPT-4.5
xAI
Grok 4.20 Beta
Overview
CompanyOpenAIxAI
Release dateFeb 27 2025Feb 17 2026
Model type
Open sourceNoNo
Specifications
Parameters
Context window
Benchmarks
Timeline
Release gapGPT-4.5 shipped 355 days before Grok 4.20 Beta

Which is better: GPT-4.5 or Grok 4.20 Beta?

GPT-4.5 and Grok 4.20 Beta don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-4.5 shipped 355 days before Grok 4.20 Beta, 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 — GPT-4.5 and Grok 4.20 Beta don't publish scores on any of the same benchmarks.

Frequently asked questions

When was GPT-4.5 released?
GPT-4.5 was released by OpenAI on Feb 27 2025.
When was Grok 4.20 Beta released?
Grok 4.20 Beta was released by xAI on Feb 17 2026.

Other comparisons