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Model comparison

GPT-5.2 Pro vs GPT-5.1 Pro

Short answer

GPT-5.2 Pro has the larger context window (400K vs 0K).

Specs and pricing side by side

SpecGPT-5.2 ProGPT-5.1 Pro
MakerOpenAIOpenAIsame
Released2025-12-112025-11-19
Context window400KGPT-5.1 Pro ran inside ChatGPT, where OpenAI did not publish a token context limit for the Pro tier. The GPT-5.1 API model it is based on uses a 400,000-token context window.
Max output128KNot separately published for the ChatGPT Pro…
Input price$1.75 / 1M tokensNo published API price
Output price$14 / 1M tokensNo published API price
ParametersNot disclosedNot disclosed by OpenAI.
LicenseProprietaryProprietary (OpenAI). Available through ChatGPT subscriptions under OpenAI's terms of use; not open-weight.
WeightsAPI onlyAPI onlysame
ModalitiesText, VisionText input, Image input, Text output
Knowledge cutoffAugust 31, 2025Not separately published for GPT-5.1 Pro. The…

Benchmarks both models report

These two models have no benchmark in common in our registry, so there is no like-for-like score to compare. See each model’s own results: GPT-5.2 Pro, GPT-5.1 Pro.

Which one should you pick?

Pick GPT-5.2 Pro if…

  • You need the longer context (400K vs 0K).
  • You need Text / Vision input, which GPT-5.1 Pro lacks.
  • Your use case is: research-grade questions where a slower, higher-quality answer is worth the wait.

Pick GPT-5.1 Pro if…

  • You need Text input / Image input / Text output input, which GPT-5.2 Pro lacks.
  • Your use case is: tackling difficult technical or scientific questions where answer quality matters more than latency.

FAQ

Which is better, GPT-5.2 Pro or GPT-5.1 Pro?

GPT-5.2 Pro has the larger context window (400K vs 0K). The better pick depends on whether you value benchmark scores, price per token, context length or openness for your workload.

What are the context windows of GPT-5.2 Pro and GPT-5.1 Pro?

GPT-5.2 Pro offers 400K with up to 128K output; GPT-5.1 Pro offers GPT-5.1 Pro ran inside ChatGPT, where OpenAI did not publish a token context limit for the Pro tier. The GPT-5.1 API model it is based on uses a 400,000-token context window. with up to Not separately published for the ChatGPT Pro tier. The GPT-5.1 API model supports up to 128,000 output tokens. output.

Is GPT-5.2 Pro newer than GPT-5.1 Pro?

GPT-5.2 Pro was released 2025-12-11; GPT-5.1 Pro was released 2025-11-19.

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