Why Fetch API Beats Ajax: Simplify Your Web Requests Today

Early web development relied on the XMLHttpRequest object (Ajax) for client‑server data exchange, but modern browsers now offer a more elegant solution that replaces traditional Ajax.

Traditional Ajax's Cumbersomeness

First, let’s review the classic Ajax implementation:

var xhr = new XMLHttpRequest();
xhr.open('GET', 'https://api.example.com/data', true);
xhr.onreadystatechange = function() {
  if (xhr.readyState === 4) {
    if (xhr.status === 200) {
      var response = JSON.parse(xhr.responseText);
      console.log(response);
    } else {
      console.error('Request failed, status code:', xhr.status);
    }
  }
};
xhr.onerror = function() {
  console.error('Request error');
};
xhr.send();

This code is verbose, requires handling many status codes and events, and results in complex, hard‑to‑read structure.

The Elegance of fetch API

In contrast, using the fetch API can greatly simplify this process:

This code uses Promise chaining, reducing the amount of code and making the logic clearer.

Key Features of fetch API

1. Promise‑Based

fetch is built on Promise, allowing the use of .then() and .catch() methods for handling asynchronous operations. It can also be combined with async/await syntax to make asynchronous code appear synchronous.

2. Simple Request Configuration

fetch allows request configuration via a second‑argument object:

3. Stream Handling

fetch returns a Response object that provides several methods for processing the response: response.json(): parse the response as JSON response.text(): parse the response as plain text response.blob(): parse the response as a Blob response.arrayBuffer(): parse the response as an ArrayBuffer response.formData(): parse the response as FormData

This makes handling various response types highly flexible.

4. Abort Requests

Using AbortController, fetch can abort ongoing requests:

Additionally, fetch natively supports Cross‑Origin Resource Sharing (CORS).

Considerations

Despite its many advantages, fetch has some points to watch:

fetch does not send cookies by default; to include them, set the credentials: 'include' option.

fetch('https://api.example.com/data', {
  credentials: 'include'
});

fetch does not automatically reject responses with status 4xx or 5xx; you need to manually check response.ok or response.status .

fetch lacks a built‑in request timeout; you must combine AbortController with setTimeout to implement one.

With its concise syntax and powerful capabilities, fetch API has become the preferred method for network requests in modern web development, solving the cumbersome issues of traditional Ajax while offering greater functionality and flexibility.