Claude 3.5 SonnetvsClaude Opus 4.1

Claude 3.5 Sonnet
Claude Opus 4.1
Benchmarks
BullshitBench v2
45%43%
SWE-Bench Verified
33.4%74.5%
GPQA Diamond
59.4%80.9%
Overview
CompanyAnthropicAnthropic
Release dateJun 20 2024Aug 5 2025
AccessProprietaryProprietary

Frequently asked questions

Claude Opus 4.1 leads Claude 3.5 Sonnet on 2 of the 3 benchmarks they both report (BullshitBench v2, SWE-Bench Verified, GPQA Diamond). Claude 3.5 Sonnet shipped 411 days before Claude Opus 4.1, 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 3.5 Sonnet leads at 45% vs Claude Opus 4.1 at 43%. On SWE-Bench Verified, Claude Opus 4.1 leads at 74.5% vs Claude 3.5 Sonnet at 33.4%. On GPQA Diamond, Claude Opus 4.1 leads at 80.9% vs Claude 3.5 Sonnet at 59.4%.

Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.

Claude Opus 4.1 was released by Anthropic on Aug 5 2025.

Claude Opus 4.1 leads on SWE-Bench Verified — Claude 3.5 Sonnet 33.4% vs Claude Opus 4.1 74.5%.

Claude Opus 4.1 leads on GPQA Diamond — Claude 3.5 Sonnet 59.4% vs Claude Opus 4.1 80.9%.

Other comparisons