Server Error

HTTP 523 Origin Is Unreachable

Cloudflare could not reach the origin server, likely due to DNS issues.

Check a URL for HTTP 523

Paste any URL to see whether it currently returns 523. Runs a live HTTP probe and follows redirects.

What does HTTP 523 mean?

HTTP 523 is a Cloudflare-specific error meaning Cloudflare cannot resolve the origin server's DNS or route to its IP address.

Common Causes

•Incorrect origin IP in Cloudflare settings
•DNS resolution failure
•Origin server IP changed
•Network routing issue

How to Fix It

1.Verify the origin IP in Cloudflare DNS settings
2.Check that DNS records are correct
3.Ensure origin server is accessible from outside

SEO Impact

Complete site outage through Cloudflare. Will be treated as downtime by search engines.

Monitor HTTP 523 with LemWatch

LemWatch monitors DNS resolution as part of its checks and can detect when origin IP changes cause reachability issues.

Related Status Codes

Web Server Is Down

Connection Timed Out

Bad Gateway

Network Authentication Required

524

A Timeout Occurred

500

Internal Server Error

523 Origin Is Unreachable on your platform

Same status code, different fix depending on where you host. Jump to a platform-specific deep dive:

523 in Cloudflare

Free Website Tools

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