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

Claude Sonnet 4.5 vs GPT-5.4 mini

Anthropic
Claude Sonnet 4.5
OpenAI
GPT-5.4 mini
Overview
CompanyAnthropicOpenAI
Release dateSep 29 2025Mar 17 2026
AccessProprietaryProprietary
Specifications
Context window
400k
Benchmarks
Nonsense detection
BullshitBench v2
79%Best
32%
Coding
SWE-Bench Verified
77.2%
Next.js coding
Next.js Evals
50%
Science
GPQA Diamond
83.4%
Multimodal
MMMU
68%
Timeline
Release gapClaude Sonnet 4.5 shipped 169 days before GPT-5.4 mini

Which is better: Claude Sonnet 4.5 or GPT-5.4 mini?

Claude Sonnet 4.5 leads GPT-5.4 mini on 1 of the 1 benchmark they both report (BullshitBench v2). Claude Sonnet 4.5 shipped 169 days before GPT-5.4 mini, 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 Sonnet 4.5 leads at 79% vs GPT-5.4 mini at 32%.

Frequently asked questions

Claude Sonnet 4.5 was released by Anthropic on Sep 29 2025.

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

Other comparisons