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

Claude Sonnet 5 vs GPT-5.6 Luna

Anthropic
Claude Sonnet 5
OpenAI
GPT-5.6 Luna
Overview
CompanyAnthropicOpenAI
Release dateJun 30 2026Jun 26 2026
AccessProprietaryProprietary
Benchmarks
Agentic coding
SWE-Bench Pro
63.2%
Agentic coding
CursorBench v3.1
61.2%
Agentic terminal coding
Terminal-Bench 2.1
80.4%
82.5%Best
Multidisciplinary reasoning
Humanity's Last Exam · no tools
43.2%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
57.4%
Agentic computer use
OSWorld-Verified
81.2%
Knowledge work
GDPval-AA
1618
Timeline
Release gapGPT-5.6 Luna shipped 4 days before Claude Sonnet 5

Which is better: Claude Sonnet 5 or GPT-5.6 Luna?

GPT-5.6 Luna leads Claude Sonnet 5 on 1 of the 1 benchmark they both report (Terminal-Bench 2.1). GPT-5.6 Luna shipped 4 days before Claude Sonnet 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 Terminal-Bench 2.1, GPT-5.6 Luna leads at 82.5% vs Claude Sonnet 5 at 80.4%.

Frequently asked questions

Claude Sonnet 5 was released by Anthropic on Jun 30 2026.

GPT-5.6 Luna was released by OpenAI on Jun 26 2026.

GPT-5.6 Luna leads on Terminal-Bench 2.1 — Claude Sonnet 5 80.4% vs GPT-5.6 Luna 82.5%.

Other comparisons