HTTP

HTTP 103 Early Hints vs 504 Gateway Timeout

HTTP 103 (Early Hints) is a 1xx Informational response, while 504 (Gateway Timeout) is a 5xx Server Error response. 103 indicates that used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response. In contrast, 504 means that the server, acting as a gateway or proxy, did not receive a timely response from the upstream server.

Description

Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.

When You See It

When a server wants the browser to start loading CSS/JS before the full response is ready.

How to Fix

No fix needed. This optimization helps speed up page loading.

Description

The server, acting as a gateway or proxy, did not receive a timely response from the upstream server.

When You See It

When an upstream server is too slow to respond within the proxy's timeout window.

How to Fix

Increase proxy timeout settings. Optimize upstream server performance. Check for long-running queries.

Key Differences

1.

103 is a 1xx Informational response, while 504 is a 5xx Server Error response.

2.

HTTP 103: Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.

3.

HTTP 504: The server, acting as a gateway or proxy, did not receive a timely response from the upstream server.

4.

You encounter 103 when when a server wants the browser to start loading CSS/JS before the full response is ready.

5.

You encounter 504 when when an upstream server is too slow to respond within the proxy's timeout window.

When to Use Which

For 103 (Early Hints): No fix needed. This optimization helps speed up page loading. For 504 (Gateway Timeout): Increase proxy timeout settings. Optimize upstream server performance. Check for long-running queries.

Learn More