GPT-5.1
FrontierClosed weightsTextReasoning
GPT-5.x family model by OpenAI.
About the GPT-5.x family
Point releases in OpenAI's GPT-5 series (5.1/5.2/5.3), each improving reasoning, reliability and instruction-following over the base GPT-5.
All GPT-5.x modelsHow this one is configured
This configuration runs in reasoning mode (thinks step-by-step before answering).
Also runs at: high effort
Effort controls how long the model thinks before answering — higher effort usually means better answers on hard problems, at the cost of speed and money. Same model underneath, so they share this page.