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SwapGPT-6 Astra
OpenAI's new GPT-6 Astra is a major chatbot model for writing and answering questions, offered to developers online.
Release page →GPT-6 Luna
OpenAI's new GPT-6 Luna model writes text and answers questions, offered to developers and not free to download.
Release page →The basics
Released
What it does
Knowledge cutoff
The latest events it learned about
Download
Where to use it
Price and limits, for developers
Input
Per million tokens
Output
Per million tokens
Cached input
Per million tokens
Context window
How much it takes in at once
Longest answer
How they score
Combined test score
Epoch Capabilities Index · Epoch AI
GPT-6 Astra scores 13 points higher, a big step.
Chat answers, by people's votes
LMArena text, adjusted for style · LMArena
In blind votes, people pick GPT-6 Astra over GPT-6 Luna about 55% of the time.
Building apps, by people's votes
LMArena WebDev · LMArena
In blind votes, people pick GPT-6 Astra over GPT-6 Luna about 75% of the time.
Green marks the better of the two on each row, red the other. Rows where one side isn't listed, or where the gap is too close to call, stay plain.
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Rankings from LMArena and Epoch AI, both CC BY 4.0, updated . Developer prices, context windows and knowledge cutoffs from the labs' own listings on models.dev and from OpenRouter. The app links go to each maker's own app when no source says exactly where the model is available.