GPT-5 series

by OpenAI

Entry point for OpenAI’s GPT-5 generation, including the Codex coding variants and the named 5.6 releases.

Versions

VersionNote
GPT-5.3 Codex[[./gpt-5-dot-3-codex
GPT-5.3 Codex Spark[[./gpt-5-dot-3-codex-spark
GPT-5.5 (+ Instant)[[./gpt-5-dot-5
GPT-5.6 Luna[[./gpt-5-dot-6-luna
GPT-5.6 Sol[[./gpt-5-dot-6-sol
GPT-5.6 Terra[[./gpt-5-dot-6-terra

Pattern

Two conventions distinguish this generation. First, named variants — 5.6 shipped as Luna, Sol
and Terra rather than numbered sub-versions, so each needs its own note. Second, stealth
testing
: releases appeared on public arenas under codenames (Hunter Alpha, Healer Alpha for
5.5) weeks before acknowledgement, so leak coverage predates launch coverage consistently.

Codex variants are tracked here but function as coding tools as much as models.