HTML Status Codes

Definition and Usage

When a browser loads your HTML page, an image, a stylesheet, or a script, the server answers with an HTTP status code—a three-digit number that says whether the request worked, redirected, or failed.

Status codes are not HTML tags. They sit in the HTTP layer around your document. As an HTML author you meet them most often as broken <a> links (404), missing <img> files, permanent URL moves (301), and custom error pages.

How a Response Looks

HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8

<!DOCTYPE html>
<html lang="en">
  <!-- your HTML document -->
</html>

Pattern: browser requests a URL → server sends a status line (200 OK, 404 Not Found, …) → headers → optional body (often your HTML).

Five Status Classes

RFC 9110 groups responses by the first digit:

Codes You See With HTML Pages

Focus on these while building and debugging sites:

2xx — Success

3xx — Redirection

4xx — Client Error

5xx — Server Error

Related Topics

Previous: language codes. Next: drag and drop. Also: <a> (broken links → 404), <img> (missing files), lang.

HTML Examples

Read real status codes with fetch(). Use Try It Yourself for a live editor.

fetch('/html/status-code')
  .then(function (response) {
    console.log(response.status);      // 200
    console.log(response.statusText);  // OK
    console.log(response.ok);          // true
  });

200
OK
true

fetch('/html/this-page-does-not-exist')
  .then(function (response) {
    console.log(response.status);  // 404
    console.log(response.ok);      // false
  });

404
false

<input type="number" id="code" value="404">
<button type="button" id="btn">Look up</button>
<pre id="out"></pre>

Code: 404
Class: 4xx — Client Error
Meaning: Not Found — page or file missing

Browser Support

All modern browsers understand standard HTTP status codes when loading HTML and assets.

Key Takeaways