Compare AI models

Specifications
Context window
1M—
API pricing
Input price
$2.00$0.20
Output price
$10.00$1.20
Cached input price
$0.20$0.02
Cheapest input
—$0.10OpenAI
Cheapest output
—$0.60OpenAI
Benchmarks
CursorBench 4.0
55.5%35.9%
Terminal-Bench 4.0
70.6%17.27%
Overview
CompanyAnthropicOpenAI
Release dateSep 28 2026Jun 26 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Sonnet 5.5 leads GPT-5.6 Luna on 2 of the 2 benchmarks they both report (CursorBench 4.0, Terminal-Bench 4.0). GPT-5.6 Luna is cheaper on both input and output: $0.20 vs $2.00 per million input tokens, and $1.20 vs $10.00 per million output tokens. Figures are base-tier rates. GPT-5.6 Luna shipped 94 days before Claude Sonnet 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 Sonnet 5.5 leads at 55.5% vs GPT-5.6 Luna at 35.9%. On Terminal-Bench 4.0, Claude Sonnet 5.5 leads at 70.6% vs GPT-5.6 Luna at 17.27%.