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

Home/Compare/Claude Sonnet 4.5 vs Composer 2

Claude Sonnet 4.5 vs Composer 2

Anthropic Claude Sonnet 4.5 vs Cursor Composer 2 — side-by-side specs.

Anthropic
Claude Sonnet 4.5
Cursor
Composer 2
Overview
CompanyAnthropicCursor
Release dateSep 29 2025Mar 20 2026
Model type
Open sourceNoNo
Specifications
Parameters
Context window
Benchmarks
Coding
SWE-Bench Verified
77.2%
Multilingual coding
SWE-Bench Multilingual
73.7%
Agentic coding
CursorBench v3.1
52.2%
Agentic terminal coding
Terminal-Bench 2.0
61.7%
Science
GPQA Diamond
83.4%
Multimodal
MMMU
68%
Timeline
Release gapClaude Sonnet 4.5 shipped 172 days before Composer 2

Which is better: Claude Sonnet 4.5 or Composer 2?

Claude Sonnet 4.5 and Composer 2 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude Sonnet 4.5 shipped 172 days before Composer 2, 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.

Direct benchmark comparisons are unavailable — Claude Sonnet 4.5 and Composer 2 don't publish scores on any of the same benchmarks.

Frequently asked questions

When was Claude Sonnet 4.5 released?
Claude Sonnet 4.5 was released by Anthropic on Sep 29 2025.
When was Composer 2 released?
Composer 2 was released by Cursor on Mar 20 2026.

Other comparisons