GPT-6 LunavsComposer 2.5

GPT-6 Luna
Composer 2.5
Specifications
Context window
1.05M
API pricing
Input price
$0.10
Output price
$0.50
Cached input price
$0.01
Benchmarks
Next.js Evals
77%81%
Benchmarks
SWE-Bench Pro
54%
SWE-Bench Multilingual
79.8%
DeepSWE 1.1
66.6%
DeepSWE 1.0
18%
Terminal-Bench 2.1
73%
Terminal-Bench 2.0
69.3%
threejseval
1059
Overview
CompanyOpenAISpaceXAI
Release dateSep 22 2026May 18 2026
AccessProprietaryProprietary

Other comparisons

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Frequently asked questions

Composer 2.5 leads GPT-6 Luna on 1 of the 1 benchmark they both report (Next.js Evals). Only GPT-6 Luna has a verified first-party API price: $0.10 per million input tokens and $0.50 per million output tokens. No pay-as-you-go API rate is tracked for Composer 2.5. Composer 2.5 shipped 127 days before GPT-6 Luna, 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 Next.js Evals, Composer 2.5 leads at 81% vs GPT-6 Luna at 77%.