GPT-5.1
OpenAI GPT-5.1 chat model (November 2025). An earlier GPT-5 point release kept available for compatibility. Good general-purpose reasoning and coding.
GPT-5.1 is text & chat AI model from OpenAI, priced at €1.25 per 1M input tokens with a 400K tokens context window.
0.7
Pricing
API Integration
Use our OpenAI-compatible API to integrate GPT-5.1 into your application.
npm install railwailimport railwail from "railwail";
const rw = railwail("YOUR_API_KEY");
// Simple — just pass a string
const reply = await rw.run("gpt-5-1", "Hello! What can you do?");
console.log(reply);
// With message history
const reply2 = await rw.run("gpt-5-1", [
{ role: "system", content: "You are a helpful assistant." },
{ role: "user", content: "Explain quantum computing simply." },
]);
console.log(reply2);
// Full response with usage info
const res = await rw.chat("gpt-5-1", [
{ role: "user", content: "Hello!" },
], { temperature: 0.7, max_tokens: 500 });
console.log(res.choices[0].message.content);
console.log(res.usage);Frequently asked questions
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