When was Claude Opus 4.5 released?

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

When was GPT-5.1 released?

GPT-5.1 was released by OpenAI on Nov 12 2025.

Which is better on GPQA Diamond, Claude Opus 4.5 or GPT-5.1?

GPT-5.1 scores higher on GPQA Diamond — Claude Opus 4.5 87% vs GPT-5.1 88.1%.

Which is better at coding, Claude Opus 4.5 or GPT-5.1?

On SWE-Bench Verified (real-world software-engineering tasks), Claude Opus 4.5 leads — Claude Opus 4.5 scores 80.9% and GPT-5.1 scores 76.3%.

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Claude Opus 4.5 vs GPT-5.1

1 vs 2 benchmarks won

	Anthropic Claude Opus 4.5	OpenAI GPT-5.1
Overview
Company	Anthropic	OpenAI
Release date	Nov 24 2025	Nov 12 2025
Model type	—	—
Open source	No	No
Specifications
Parameters	—	—
Context window	—	—
Benchmarks
Science reasoning GPQA Diamond	87%	88.1%
Software engineering SWE-Bench Verified	80.9%	76.3%
Multimodal understanding MMMU	—	76%
Timeline
Release gap	GPT-5.1 shipped 12 days before Claude Opus 4.5

Which is better: Claude Opus 4.5 or GPT-5.1?

GPT-5.1 leads Claude Opus 4.5 on 2 of the tracked benchmarks (GPQA Diamond, SWE-Bench Verified, MMMU). GPT-5.1 shipped 12 days before Claude Opus 4.5, 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 GPQA Diamond, GPT-5.1 scores 88.1%, 1.1 points above Claude Opus 4.5 at 87%. On SWE-Bench Verified, Claude Opus 4.5 scores 80.9%, 4.6 points above GPT-5.1 at 76.3%.

Frequently asked questions

When was Claude Opus 4.5 released?: Claude Opus 4.5 was released by Anthropic on Nov 24 2025.
When was GPT-5.1 released?: GPT-5.1 was released by OpenAI on Nov 12 2025.
Which is better on GPQA Diamond, Claude Opus 4.5 or GPT-5.1?: GPT-5.1 scores higher on GPQA Diamond — Claude Opus 4.5 87% vs GPT-5.1 88.1%.
Which is better at coding, Claude Opus 4.5 or GPT-5.1?: On SWE-Bench Verified (real-world software-engineering tasks), Claude Opus 4.5 leads — Claude Opus 4.5 scores 80.9% and GPT-5.1 scores 76.3%.