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HTTP 524 — A Timeout Occurred

HTTP 524
A Timeout Occurred
Cloudflare connected to the origin successfully but the origin did not finish responding in time.

What 524 actually means

Cloudflare's own code, not part of HTTP — effectively their version of a 504. The TCP connection was established and the request was delivered, but the origin did not send a complete response within Cloudflare's proxy read timeout, which defaults to 125 seconds. It always means the origin is running but slow: a long query, a heavy report, or a request waiting on something that never came back.

Common causes

  • A request taking longer than Cloudflare's default 125-second proxy read timeout
  • A slow database query or an unindexed table scan
  • A long-running export, import or report generation done synchronously
  • A WebSocket or long-polling connection idling past the timeout
  • An origin waiting on a third-party API that never answers

If you're just trying to view the page

  1. Retry — if the operation is heavy, it may succeed when the server is less busy
  2. If you triggered a large export or report, try a smaller range
  3. Nothing else; the site's server needs to answer faster

If it's your site

  1. Move work that takes longer than a few seconds into a background job and return immediately with a status URL
  2. Profile and fix the slow path — the 125-second timeout is not adjustable below Enterprise
  3. Enterprise plans can raise the proxy read timeout as far as 6,000 seconds, but that is a workaround rather than a fix
  4. For long-lived connections, use Cloudflare's WebSocket support rather than long-polling over plain HTTP
  5. Consider routing the slow endpoint around Cloudflare on a grey-clouded (DNS-only) subdomain if it genuinely must run long

Reference

Status code
524
Reason phrase
A Timeout Occurred
Category
5xx — Server Error
Cacheable by default
No

Common questions

What does HTTP 524 mean?
Cloudflare connected to the origin successfully but the origin did not finish responding in time. Cloudflare's own code, not part of HTTP — effectively their version of a 504. The TCP connection was established and the request was delivered, but the origin did not send a complete response within Cloudflare's proxy read timeout, which defaults to 125 seconds.
How do I fix a 524 error?
Retry — if the operation is heavy, it may succeed when the server is less busy
Is 524 a client error or a server error?
524 is in the 5xx range, which means server error. The request was acceptable but the server could not fulfil it, so retrying later can succeed.

Related pages

Sources

  1. Hypertext Transfer Protocol (HTTP) Status Code Registry — IANA
  2. RFC 9110: HTTP Semantics — IETF

How these figures are compiled and checked