GPT-5.6 Luna vs GPT-5.6 Sol

GPT-5.6 Luna (OpenAI) vs GPT-5.6 Sol (OpenAI), compared on price, context, speed and Arabic support. Both run on thalam through one OpenAI-compatible API, so you can switch between them with a single model id change. At a glance, GPT-5.6 Luna is the cheaper option and GPT-5.6 Luna is rated faster.

Specs side by side

SpecGPT-5.6 LunaGPT-5.6 Sol
ProviderOpenAIOpenAI
TypeTextText
Context window1M1M
Max output128K128K
Input price$0.20 / 1M$5.00 / 1M
Output price$1.20 / 1M$30.00 / 1M
SpeedFastMedium
Arabic supportStrongStrong

Which should you choose?

Choose GPT-5.6 Luna if…
  • Lower cost, about 25× cheaper ($0.20 / 1M)
  • Rated faster (Fast) for latency-sensitive workloads
Choose GPT-5.6 Sol if…
  • The top tier of OpenAI's GPT-5.6 generation. Frontier reasoning, coding, and agentic work with a 1M-token context and image input
Run both GPT-5.6 Luna and GPT-5.6 Sol on one API

One OpenAI-compatible endpoint, one bill. Switch between them with a single model id change, pay per use, credits never expire.

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FAQ

What's the difference between GPT-5.6 Luna and GPT-5.6 Sol?

GPT-5.6 Luna costs less ($0.20 / 1M vs $5.00 / 1M); GPT-5.6 Luna is rated faster. Both are available on thalam behind one OpenAI-compatible API.

Is GPT-5.6 Luna or GPT-5.6 Sol cheaper?

GPT-5.6 Luna is cheaper on input ($0.20 / 1M vs $5.00 / 1M). On thalam you pay per use, so you can route cheap-by-default and fall back to the other only when needed.

Can I use both GPT-5.6 Luna and GPT-5.6 Sol with one API key?

Yes. thalam is OpenAI-compatible, so both models are reachable through the same endpoint. Switching between them is a one-line model id change, no code rewrite.