Convert cURL to JavaScript

Generate browser-ready JavaScript code from cURL commands. Supports both modern Fetch API and legacy XMLHttpRequest for maximum compatibility.

Quick Example

Convert this cURL command:

curl -X GET https://api.example.com/users/123 \
  -H "Authorization: Bearer YOUR_TOKEN"

Into JavaScript (Fetch):

fetch('https://api.example.com/users/123', {
  method: 'GET',
  headers: {
    'Authorization': 'Bearer YOUR_TOKEN'
  }
})
  .then(response => response.json())
  .then(data => console.log(data));

Fetch vs XMLHttpRequest

Common Patterns

POST with JSON Body

curl -X POST https://api.example.com/login \
  -H "Content-Type: application/json" \
  -d '{"username":"user","password":"pass"}'

Converts to:

fetch('https://api.example.com/login', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    username: 'user',
    password: 'pass'
  })
})
  .then(response => response.json())
  .then(data => console.log(data));

With Async/Await

async function login() {
  try {
    const response = await fetch('https://api.example.com/login', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        username: 'user',
        password: 'pass'
      })
    });
    const data = await response.json();
    console.log(data);
  } catch (error) {
    console.error('Error:', error);
  }
}

File Upload with FormData

curl -X POST https://api.example.com/upload \
  -F "[email protected]" \
  -F "title=My Photo"

Converts to:

const formData = new FormData();
formData.append('file', fileInput.files[0]);
formData.append('title', 'My Photo');

fetch('https://api.example.com/upload', {
  method: 'POST',
  body: formData
})
  .then(response => response.json())
  .then(data => console.log(data));

Browser Compatibility

• Fetch API: Chrome 42+, Firefox 39+, Safari 10.1+, Edge 14+
• XMLHttpRequest: All browsers including IE6+

Try It Live

Open the converter to transform your cURL commands, or use RequestBin to test the code with real endpoints.

Related docs: Python | Node.js | Headers & JSON