error code 303

HTTP Status Code 303 = “See Other”

It tells the client:

“The requested resource can be found at another URL using a GET request.”

The server redirects the browser to a different URL after processing a request.

Common use case

303 is commonly used after:

  • form submissions,
  • file uploads,
  • POST requests,
  • payment processing,
  • login/authentication flows.

It prevents users from resubmitting forms when refreshing the page.

Example flow

Client sends POST

http id=”v8d2qx”
POST /submit-form HTTP/1.1

Server response

http id=”f3k7nt”
HTTP/1.1 303 See Other
Location: /success

Browser automatically performs

http id=”q9m1yc”
GET /success HTTP/1.1

Difference between 302 and 303

| Code | Behavior |
| — | |
| 302 | Redirect, method may stay same |
| 303 | Always redirect using GET |

Common scenarios

  • Payment gateway redirects
  • OAuth login flow
  • REST APIs
  • Form submission success page
  • Checkout confirmation page Developer examples

PHP

php id=”u4p9rb”
header(“Location: /success”, true, 303);
exit;

Node.js Express

js id=”a7t5zn”
res.redirect(303, ‘/success’);

Laravel

php id=”j2k8we”
return redirect(‘/success’, 303);

Why use 303?

It follows the Post/Redirect/Get (PRG) pattern:

  1. User submits form (POST)
  2. Server processes request
  3. Server redirects (303)
  4. Browser loads success page (GET)

This avoids duplicate form submissions.

Related redirect codes

| Code | Meaning |
| — | |
| 301 | Permanent Redirect |
| 302 | Temporary Redirect |
| 303 | See Other |
| 307 | Temporary Redirect |
| 308 | Permanent Redirect |