# axios — Promise-Based HTTP Client for Browser & Node.js

> axios is the most popular HTTP client for JavaScript — promise-based, isomorphic (browser + Node), with request/response interceptors, automatic JSON transforms, CSRF protection, and built-in cancellation. Battle-tested since 2014.

## Install

Save in your project root:

## Quick Use

```bash
npm i axios
```

```ts
import axios from "axios";

// GET
const { data } = await axios.get("https://api.github.com/users/williamwangai");

// POST with JSON body
await axios.post("/api/users", { name: "William", email: "w@example.com" });

// Create instance with defaults
const api = axios.create({
  baseURL: "https://api.tokrepo.com",
  headers: { Authorization: `Bearer ${token}` },
  timeout: 10000,
});

api.interceptors.response.use(
  (res) => res,
  (err) => {
    if (err.response?.status === 401) location.href = "/login";
    return Promise.reject(err);
  }
);
```

## Intro

axios is the most popular HTTP client for JavaScript — promise-based, isomorphic (works in browser and Node.js with the same API), battle-tested since 2014. Despite the modern `fetch()` API being available everywhere, axios still ships in 100M+ weekly npm installs for its superior DX.

- **Repo**: https://github.com/axios/axios
- **Stars**: 108K+
- **License**: MIT

## What axios Does

- **Promise API** — async/await friendly
- **Isomorphic** — same code browser + Node.js
- **Interceptors** — transform requests/responses globally
- **Auto JSON** — serializes request body, parses response
- **Timeouts** — `timeout` option
- **Cancellation** — `AbortController` support
- **Progress events** — upload/download progress
- **XSRF protection** — cookie-based CSRF token
- **Instance config** — `axios.create({ baseURL, headers })`

## Architecture

Wraps `XMLHttpRequest` in browsers and `http`/`https` modules in Node.js. Request goes through interceptor chain → adapter → transformer → promise. Error is a normal rejected promise with `err.response`/`err.request` for inspection.

## Self-Hosting

Client library only.

## Key Features

- Isomorphic (browser + Node)
- Request/response interceptors
- Automatic JSON transforms
- Form data & multipart support
- Streaming in Node.js
- Cancellation via AbortController
- Progress events (uploads)
- TypeScript types built in
- AbortController and signal support

## Comparison

| Client | Isomorphic | Interceptors | Auto JSON | Bundle |
|---|---|---|---|---|
| axios | Yes | Yes | Yes | ~14KB |
| fetch | Yes (modern) | No (manual) | No (manual) | 0 |
| ky | Yes (modern) | Yes | Yes | ~5KB |
| ofetch | Yes | Limited | Yes | ~4KB |
| got | Node only | Yes | Yes | ~40KB |

## FAQ

**Q: fetch is good enough — why still use axios?**
A: fetch doesn't auto-parse JSON, doesn't auto-throw on HTTP errors, has no interceptors, and isn't supported in older Node versions. axios saves time out of the box.

**Q: How do I cancel a request?**
A: `const controller = new AbortController(); axios.get(url, { signal: controller.signal }); controller.abort();`

**Q: How do I handle CSRF?**
A: axios reads the `XSRF-TOKEN` cookie by default and puts it in the `X-XSRF-TOKEN` header, matching the CSRF mechanisms used by Rails/Laravel.

## Sources & Credits

- Docs: https://axios-http.com
- GitHub: https://github.com/axios/axios
- License: MIT

---
Source: https://tokrepo.com/en/workflows/axios-promise-based-http-client-browser-node-js-b3e550af
Author: AI Open Source