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

Claude Opus 4.5 vs GPT-5.4 nano

Anthropic
Claude Opus 4.5
OpenAI
GPT-5.4 nano
Overview
CompanyAnthropicOpenAI
Release dateNov 24 2025Mar 17 2026
AccessProprietaryProprietary
Benchmarks
Nonsense detection
BullshitBench v2
90%Best
14%
Coding
SWE-Bench Verified
80.9%
Science
GPQA Diamond
87%
Timeline
Release gapClaude Opus 4.5 shipped 113 days before GPT-5.4 nano

Which is better: Claude Opus 4.5 or GPT-5.4 nano?

Claude Opus 4.5 leads GPT-5.4 nano on 1 of the 1 benchmark they both report (BullshitBench v2). Claude Opus 4.5 shipped 113 days before GPT-5.4 nano, 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.

On BullshitBench v2, Claude Opus 4.5 leads at 90% vs GPT-5.4 nano at 14%.

Frequently asked questions

Claude Opus 4.5 was released by Anthropic on Nov 24 2025.

GPT-5.4 nano was released by OpenAI on Mar 17 2026.

Other comparisons