Pyyan / Compare / GPT-5.6 Luna vs GPT-6 Astra

GPT-5.6 Luna vs GPT-6 Astra

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Language Models · verified 5 Sept 2026

GPT-5.6 LunaOpenAIcurrent
GPT-6 AstraOpenAIcurrent
3 slots left
SpecificationGPT-5.6 LunaGPT-6 Astra
SummaryFastest and cheapest GPT-5.6 tier.Saturates three of the benchmarks it reports, and ships disabled for enterprise.
Context1M+1.05M
Input ($/Mtok)—$10
Output ($/Mtok)—$50
LicenceProprietaryProprietary
Max output—128K
Parameters—Not published
Released—3 Sep 2026
Model ID—gpt-6-astra
CategoryLanguage ModelsLanguage Models
OfficialOpenAI ↗—

Highlighted rows are where these differ.

GPT-5.6 Luna

Fastest and cheapest GPT-5.6 tier.

Best for high volume.

Full spec sheet →

GPT-6 Astra

  • 97.6% on FrontierMath Tier 4, 99.9% on ARC-AGI-3 and 100% on ExploitBench
  • Above 272K input tokens the whole request reprices: input and cache at 2x, output at 1.5x
  • Rolls out to OpenAI's Daybreak cyber programme first, and arrives switched off for enterprise

Best for hard reasoning and computer use.

Full spec sheet →