1xx Informational

HTTP 103 Early Hints

Used to preload resources while the server prepares a response by sending Link headers early.

When is 103 used?

  • Preloading CSS/JS before final response
  • Hinting the browser to start fetching critical resources

How to handle a 103 response

Clients rarely see these directly; HTTP libraries handle them before the final response arrives, and servers usually send them automatically.

Check the status code a URL returns from the command line:

curl -s -o /dev/null -w "%{http_code}\n" https://example.com

Frequently Asked Questions

What does HTTP 103 mean?

103 Early Hints: Used to preload resources while the server prepares a response by sending Link headers early.

Is 103 an error?

No. 103 is in the 1xx Informational class. Informational responses: the request was received and processing continues.