GPT-5.1 is a top model in OpenAI’s GPT-5 series, with better general reasoning, better instruction following, and a more natural conversational tone than GPT-5. Adaptive reasoning adjusts its computational effort: it responds quickly to simple queries and works longer on complex tasks. Explanations are clearer and use less jargon. It improves on math, coding, and structured analysis, with more cohesive long-form responses and more reliable tool use. Its conversation style is warmer but still precise. GPT-5.1 is the main, fully capable successor to GPT-5.
$0.625
$0.0625
$5.00
Throughput is how fast the model writes (tokens per second, higher is better). Time to first token is how long before the answer starts (lower is better).
Share of requests served without a server error. Client errors (4xx) do not count.
Works with the OpenAI SDK pointed at our base URL. Every parameter is in the API reference.
Tokens processed per day on NagaAI.
GPT-5.1 is a top model in OpenAI’s GPT-5 series, with better general reasoning, better instruction following, and a more natural conversational tone than GPT-5. Adaptive reasoning adjusts its computational effort: it responds quickly to simple queries and works longer on complex tasks.
On NagaAI, GPT 5.1 costs $0.625 per 1M input tokens and $5 per 1M output tokens. You pay only for what you use, with no subscription.
GPT 5.1 reads up to 400k tokens in one request, counting the prompt and the answer together.
Yes. GPT 5.1 can call your functions as tools and can answer in a JSON schema you give it.
It takes text, images and files as input and returns text.
Create an API key, copy the model ID from the top of this page and send requests with the OpenAI or Anthropic SDK pointed at NagaAI. The API section on this page has a ready example.
GPT-6.1 TerraOpenAIGPT-6.1 SolOpenAIGPT-6 LunaOpenAIGPT-6 SolOpenAIGPT-6 AstraOpenAIGPT 5.6 LunaOpenAINot enough throughput data
Not enough TTFT data