HTTP 504 Gateway Timeout

What does HTTP 504 mean?

A gateway or proxy did not get a response from the upstream server in time. The application is reachable but too slow: the proxy gives up after its timeout (60 s by default in Nginx proxy_read_timeout; 100 s at Cloudflare; 10–60 s on serverless platforms).

5xx Server error: The request looked valid, but the server failed to fulfil it. The fix is on the server side.

Common causes of a 504 error

• Slow database queries or external API calls.
• Long-running requests such as reports or imports done synchronously.
• Serverless function time limits.

How to fix 504 Gateway Timeout

• Optimise slow queries and add caching.
• Move long tasks to background jobs and return 202.
• Raise proxy timeouts only as a last resort.

504 and SEO

Slow responses hurt Core Web Vitals and crawling; persistent 504s cause deindexing like other 5xx errors.

Example response

HTTP/1.1 504 Gateway Timeout

Related status codes

• 502 Bad Gateway — A gateway or proxy got an invalid response from the upstream server.
• 503 Service Unavailable — The server is temporarily unable to handle the request.
• 408 Request Timeout — The server timed out waiting for the client to send the request.
• 524 A Timeout Occurred — Cloudflare connected to the origin, but it did not send a response within 100 seconds.

Check which status code a URL returns with the HTTP header checker.