504 Gateway Timeout

HTTP response status code 504 Gateway Timeout is a server error indicating the server, while acting as a gateway or proxy, did not receive a timely response from the upstream server.

Table of Contents

Usage

The 504 Gateway Timeout status code means the server is acting as a proxy or gateway for an upstream server. After receiving the HTTP request, the server attempted to forward the request to the upstream server but received no response within the allowed time.

This is related to the 502 Bad Gateway status code. A 502 indicates the upstream server returned an invalid response, while a 504 indicates no response was received at all.

Platform-specific timeouts vary. The Shopify API enforces a 10-second request timeout and returns 504 Gateway Timeout when a response is not ready within the window. Developers working with the Shopify API must optimize queries and use background processing for operations exceeding this limit.

SEO impact

Googlebot treats 5xx errors as a signal to temporarily reduce the crawl rate across the site. Previously indexed URLs are preserved initially, but extended downtime causes Google to drop them from the index. Any content returned with a 504 response is ignored. Google explicitly groups 500, 502, and 503 together as server errors in its documentation. A 504 is not explicitly included in the grouping but is likely treated similarly as a general 5xx error. A 5xx error on the robots.txt file is far more severe, even when every other page on the site returns 200. Google halts crawling for up to 12 hours, then falls back to a cached copy for up to 30 days. If the error persists, Google fully deindexes the site. Bingbot also treats 5xx responses as crawl failures. Persistent 5xx errors prevent indexing in Bing.

Example

The client requests a resource and the server responds with a 504 Gateway Timeout status code because the upstream server did not return an HTTP response.

Request

GET /news HTTP/1.1
Host: www.example.re

Response

HTTP/1.1 504 Gateway Timeout
Content-Type: text/html; charset=UTF-8
Content-Length: 128

<html>
  <head>
    <title>Gateway Timeout</title>
  </head>
  <body>
    <p>The server is not responding.</p>
  </body>
</html>

How to fix

The proxy timed out waiting for the backend to respond. The fix is either raising the timeout or making the backend faster.

Increase proxy timeouts.

In nginx, the default timeout is 60 seconds. Raise the relevant directives in the server or location block:

  • proxy_read_timeout 300; for reverse proxy setups using proxy_pass
  • fastcgi_read_timeout 300; for PHP-FPM setups using fastcgi_pass
  • proxy_connect_timeout 60; and proxy_send_timeout 300; also warrant review

In Apache, set ProxyTimeout 300 in the virtual host or global configuration. When using mod_proxy_fcgi, the timeout parameter on the ProxyPassMatch directive controls the wait.

Align backend timeouts. The backend process needs a matching or higher timeout. For PHP, raise max_execution_time in php.ini and request_terminate_timeout in the PHP-FPM pool configuration. For Node.js, set server.timeout. For Gunicorn, use --timeout.

Optimize the slow backend operation. A timeout is a symptom of a slow operation. Profile the request to find the bottleneck:

  • Slow database queries: add indexes, reduce result sets, or move heavy work to a background job queue
  • External API calls: add timeouts and circuit breakers so a stalled third-party service does not block the entire request
  • Large file processing: stream the response instead of buffering the entire result

Respect platform-imposed timeouts. Hosted platforms enforce hard limits shorter than typical proxy defaults. Shopify imposes a 10-second ceiling. For operations exceeding the platform limit, offload work to background jobs and poll for results instead of blocking the HTTP request.

Check network path. Verify connectivity between the proxy and backend with curl or telnet. Packet loss, DNS delays, or firewall rules on intermediate hops all contribute to timeouts. Run traceroute to identify slow network segments.

Add Caching. For idempotent requests, Caching the response at the proxy layer avoids repeated slow backend calls. Nginx proxy_cache_path and Apache mod_cache both reduce upstream load.

Code references

.NET

HttpStatusCode.GatewayTimeout

Rust

http::StatusCode::GATEWAY_TIMEOUT

Rails

:gateway_timeout

Go

http.StatusGatewayTimeout

Symfony

Response::HTTP_GATEWAY_TIMEOUT

Python3.5+

http.HTTPStatus.GATEWAY_TIMEOUT

Java

java.net.HttpURLConnection.HTTP_GATEWAY_TIMEOUT

Apache HttpComponents Core

org.apache.hc.core5.http.HttpStatus.SC_GATEWAY_TIMEOUT

Angular

@angular/common/http/HttpStatusCode.GatewayTimeout

Takeaway

The 504 Gateway Timeout status code is a server error indicating an upstream server did not respond in time and the HTTP request was not completed.

See also

Last updated: March 5, 2026