gpt-5.1-2025-11-13Snapshot version of GPT-5.1 for reproducible outputs.
Pinned model version
Consistent results
Ready for deployment
Predictable behavior
View complete API reference with all parameters and examples.
Enable real-time streaming responses with Server-Sent Events.
{
"model": "gpt-5.1-2025-11-13",
"stream": true,
"messages": [...]
}Enable the model to use tools and call functions.
{
"model": "gpt-5.1-2025-11-13",
"tools": [{
"type": "function",
"function": {
"name": "get_weather",
"description": "Get current weather for a location",
"parameters": {
"type": "object",
"properties": {
"location": {"type": "string", "description": "City name"}
},
"required": ["location"]
}
}
}],
"messages": [{"role": "user", "content": "What's the weather in Tokyo?"}]
}Get structured JSON responses from the model.
{
"model": "gpt-5.1-2025-11-13",
"response_format": {"type": "json_object"},
"messages": [{"role": "user", "content": "Extract info as JSON: John is 30 years old"}]
}| Parameter | Type | Required | Description |
|---|---|---|---|
| model | string | Yes | Model identifier (e.g., gpt-5.1-2025-11-13) |
| messages | array | Yes | Array of message objects with role and content |
| max_tokens | integer | No | Maximum tokens in the response |
| stream | boolean | No | Enable streaming responses (SSE) |
| temperature | number | No | Sampling temperature (0.0 - 2.0) |
| top_p | number | No | Nucleus sampling threshold (0.0 - 1.0) |
| tools | array | No | Function calling tools definition |
| response_format | object | No | Output format (e.g., json_object) |
View complete API reference with streaming, thinking, and more.
Billing: Cost = (input_tokens * input_price + output_tokens * output_price) / 1,000,000
GPT-5.1 (2025-11-13) is a Large Language Model API provided by OpenAI. Snapshot version of GPT-5.1 for reproducible outputs. Through API Models platform, you can access this model via a unified API at prices significantly lower than official rates. Current pricing: Input: $0.265, Output: $2.206 per 1M tokens.
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GPT-5.1 (2025-11-13) is available through API Models at: Input: $0.265, Output: $2.206 per 1M tokens. This is up to 95% cheaper than official pricing.
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