HTTP 523 Origin Is Unreachable

What does HTTP 523 mean?

Cloudflare could not reach the origin server at all. Usually a DNS or routing problem: the origin IP in Cloudflare’s DNS settings is wrong, or the network path to it is broken.

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 523 error

• The A/AAAA record in Cloudflare points to an old or wrong IP.
• The hosting provider has a network outage.
• A firewall drops Cloudflare’s IP ranges.

How to fix 523 Origin Is Unreachable

• Check the DNS records in the Cloudflare dashboard against your host’s current IP.
• Ask your host whether the server is reachable, and allow Cloudflare’s IP ranges.

523 and SEO

While it lasts, crawlers can’t reach the site; fix it quickly to avoid losing rankings.

Example response

HTTP/1.1 523 Origin Is Unreachable

Related status codes

• 521 Web Server Is Down — Cloudflare could not connect to the origin server — the connection was refused.
• 522 Connection Timed Out — Cloudflare timed out while connecting to the origin server.
• 502 Bad Gateway — A gateway or proxy got an invalid response from the upstream server.

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