Compare AI models

Specifications
Context window
1M—
API pricing
Input price
$4.00—
Output price
$20.00—
Cached input price
$0.20—
Cheapest input
$4.00Amazon Bedrock—
Cheapest output
$20.00Amazon Bedrock—
Benchmarks
CursorBench 4.0
57.8%27.7%
Next.js Evals
97%81%
threejseval
20651071
Overview
CompanyAnthropicSpaceXAI
Release dateSep 22 2026May 18 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Opus 5.5 leads Composer 2.5 on 3 of the 3 benchmarks they both report (CursorBench 4.0, Next.js Evals, threejseval). Only Claude Opus 5.5 has a verified first-party API price: $4.00 per million input tokens and $20.00 per million output tokens. No pay-as-you-go API rate is tracked for Composer 2.5. Composer 2.5 shipped 127 days before Claude Opus 5.5, 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 CursorBench 4.0, Claude Opus 5.5 leads at 57.8% vs Composer 2.5 at 27.7%. On Next.js Evals, Claude Opus 5.5 leads at 97% vs Composer 2.5 at 81%. On threejseval, Claude Opus 5.5 leads at 2065 vs Composer 2.5 at 1071.