cURL to Axios (Node.js) Converter

Convert curl to axios for Node.js

This curl to axios converter rewrites a curl command as a single axios({...}) call for Node.js. Instead of copying the full URL and a raw body string, it splits the request into the fields axios expects: url, params for the query string, headers, data, auth and timeout. The result uses ES module imports and top-level await.

Example: file upload with -F

For curl -F 'title=Q3 report' -F 'file=@report.pdf' -H 'X-Api-Key: YOUR_KEY' -L https://api.example.com/uploads you get:

import axios from 'axios';
import fs from 'node:fs';
import FormData from 'form-data';

const form = new FormData();
form.append('title', 'Q3 report');
form.append('file', fs.createReadStream('report.pdf'));

const response = await axios({
  method: 'post',
  url: 'https://api.example.com/uploads',
  headers: {
    ...form.getHeaders(),
    'X-Api-Key': 'YOUR_KEY',
  },
  data: form,
});

The form-data package streams the file from disk, and form.getHeaders() supplies the multipart Content-Type with its boundary.

How curl maps to the axios config

• Query string: ?page=2&sort=name is moved into a params object, which axios encodes for you. When a key repeats (?tag=a&tag=b), the full URL is kept and no params object is written.
• JSON body: when the Content-Type is application/json and the body parses, data becomes a JavaScript object and the redundant Content-Type header is dropped, because axios sets it automatically for objects.
• Other bodies: form-encoded or plain text data stays a string in data.
• Basic auth: -u user:pass becomes auth: { username, password }.
• Timeout: --max-time 30 is converted to milliseconds, timeout: 30000.
• Redirects: axios follows redirects in Node by default, so maxRedirects: 0 is added when the command has no -L.
• TLS: -k adds an httpsAgent with rejectUnauthorized: false. Use it only for local testing.

Working with the axios response

curl prints the body and stops; with axios you get a response object to work with. The most useful parts:

console.log(response.status);                   // 200
console.log(response.headers['content-type']);  // header names are lowercase
console.log(response.data);                     // JSON is already parsed

Two adjustments are common after converting:

• Downloading a file (what curl -o does): add responseType: 'stream' to the config and pipe response.data into fs.createWriteStream('out.zip'). Without it, binary data is decoded as text and corrupted.
• Keeping 4xx and 5xx responses instead of catching them: add validateStatus: () => true, then check response.status yourself, which is closer to how curl behaves.

Limitations

The output targets Node.js. In a browser, httpsAgent, maxRedirects and the form-data package do not apply; use the native FormData and let the browser handle redirects. Proxy flags and client certificates are not converted, and unsupported options are listed as comments above the code. Keep in mind that axios rejects the promise for non-2xx status codes, so wrap the call in try/catch and read error.response for API errors.

Privacy

Everything is converted in your browser, so API keys in the command stay on your device. Prefer the built-in fetch? Use curl to JavaScript. To test the request before writing code, try the API tester, and generate typings for the response with JSON to TypeScript.