GPT-4.1

New
Popular
OpenAI
Text & Chat

OpenAI's newest flagship model. Improved reasoning, instruction following, and coding over GPT-4o.

Examples

See what GPT-4.1 can generate

System Design

Design a URL shortener service. What are the key components and how would you handle 10 million requests per day?

A URL shortener at 10M req/day needs: 1) An API layer behind a load balancer to accept long URLs and return short codes. 2) A base62 encoding scheme (a-z, A-Z, 0-9) generating 6-character codes, yielding 56 billion unique URLs. 3) A distributed key-value store like Redis for fast lookups with a persistent database (PostgreSQL) as the source of truth. 4) A caching layer (CDN + Redis) since reads vastly outnumber writes. 5) Rate limiting per IP/API key to prevent abuse. At ~115 req/sec average, a few application servers with horizontal scaling can handle the load comfortably.

Instruction Following

Write exactly 3 sentences about black holes. Each sentence must contain exactly 10 words. Do not use the word 'space'.

Black holes form when massive stars collapse under their gravity. Light cannot escape the intense gravitational pull they create. Scientists study these mysterious objects using powerful telescopes and math.

Try GPT-4.1

0.7

Response will appear here...

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Pricing

Price per Generation
Per generationFree

API Integration

Use our OpenAI-compatible API to integrate GPT-4.1 into your application.

Install
npm install railwail
JavaScript / TypeScript
import railwail from "railwail";

const rw = railwail("YOUR_API_KEY");

// Simple — just pass a string
const reply = await rw.run("gpt-4-1", "Hello! What can you do?");
console.log(reply);

// With message history
const reply2 = await rw.run("gpt-4-1", [
  { 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-4-1", [
  { role: "user", content: "Hello!" },
], { temperature: 0.7, max_tokens: 500 });
console.log(res.choices[0].message.content);
console.log(res.usage);
Specifications
Context window
1,000,000 tokens
Max output
32,768 tokens
Avg. latency
2.5s
Provider
OpenAI
Category
Text & Chat
Tags
popular
coding
reasoning
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