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AI models · OpenAI

GPT-6 Luna

Out since . The cheap GPT-6, at ten cents a million in. Oddly, it has the newest knowledge cutoff of the three: May 18, 2026.

What we've written about GPT-6 Luna

September 23, 2026

Codex models and plans explained: GPT-6 Astra, Sol and Luna, and which plan gets which

Pick any GPT-6 model you like on your laptop, but a Codex cloud task on a ChatGPT plan still runs on last generation's Sol.

September 23, 2026

Claude Code vs Codex vs Gemini CLI: which plan you need and which models you get

One of the three stopped serving individual subscribers in June, but its own docs still advertise the free tier it closed.

September 23, 2026

OpenAI model release dates: o3, GPT-5.5 and GPT-6 Astra, Sol and Luna in order

o3 is from April 2025, and the name Sol now means something different from what it meant in July.

September 22, 2026

OpenAI's GPT-6 Sol costs a fifth of Astra per token, and Luna a hundredth

Sam Altman says the pair beats the 5.6 models at half the price per token, and OpenAI's own docs still send new users to Astra first.

What is GPT-6 Luna?

GPT-6 Luna is a model from OpenAI, built in the US. It's out, and you can use it today.

When did GPT-6 Luna come out?

OpenAI released it on September 22, 2026. That date comes from the lab's own docs.

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