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

Home/Compare/Claude Opus 4.1 vs Claude Sonnet 4.5

Claude Opus 4.1 vs Claude Sonnet 4.5

0 vs 3 benchmarks won

Anthropic
Claude Opus 4.1
Anthropic
Claude Sonnet 4.5
Overview
CompanyAnthropicAnthropic
Release dateAug 5 2025Sep 29 2025
Model type
Open sourceNoNo
Specifications
Parameters
Context window
Benchmarks
Science reasoning
GPQA Diamond
80.9%
83.4%
Software engineering
SWE-Bench Verified
74.5%
77.2%
Multimodal understanding
MMMU
68%
Timeline
Release gapClaude Opus 4.1 shipped 55 days before Claude Sonnet 4.5

Which is better: Claude Opus 4.1 or Claude Sonnet 4.5?

Claude Sonnet 4.5 leads Claude Opus 4.1 on 3 of the tracked benchmarks (GPQA Diamond, SWE-Bench Verified, MMMU). Claude Opus 4.1 shipped 55 days before Claude Sonnet 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, Claude Sonnet 4.5 scores 83.4%, 2.5 points above Claude Opus 4.1 at 80.9%. On SWE-Bench Verified, Claude Sonnet 4.5 scores 77.2%, 2.7 points above Claude Opus 4.1 at 74.5%.

Frequently asked questions

When was Claude Opus 4.1 released?
Claude Opus 4.1 was released by Anthropic on Aug 5 2025.
When was Claude Sonnet 4.5 released?
Claude Sonnet 4.5 was released by Anthropic on Sep 29 2025.
Which is better on GPQA Diamond, Claude Opus 4.1 or Claude Sonnet 4.5?
Claude Sonnet 4.5 scores higher on GPQA Diamond — Claude Opus 4.1 80.9% vs Claude Sonnet 4.5 83.4%.
Which is better at coding, Claude Opus 4.1 or Claude Sonnet 4.5?
On SWE-Bench Verified (real-world software-engineering tasks), Claude Sonnet 4.5 leads — Claude Opus 4.1 scores 74.5% and Claude Sonnet 4.5 scores 77.2%.

Other comparisons