Cloudflare error codes

This error indicates a problem with your origin web server, preventing it from fulfilling the request. The Error establishing database connection message is a common HTTP 500 error, typically indicating an origin web server issue. If you encounter this error, contact your hosting provider for assistance.

Cloudflare Workers returns a 501 error when a request uses an HTTP method that is not supported by the Workers Runtime. - A client sent a request to a Workers script using a custom or non-standard HTTP method (methods outside of GET, POST, PUT, etc.). - A typo in the HTTP method (for example, POT instead of POST).

An HTTP 502 or 504 error indicates that Cloudflare is unable to establish contact with your origin web server. There are two possible causes:

HTTP error 503 occurs when your origin web server is overloaded. There are different causes identifiable by the error message or the location of the error:

An HTTP 502 or 504 error indicates that Cloudflare is unable to establish contact with your origin web server. There are two possible causes:

This error occurs when the origin server returns an empty, unknown, or unexpected response to Cloudflare. This error is often triggered by:

Error 521 occurs when the origin web server refuses connections from Cloudflare. Security solutions at your origin may block legitimate connections from certain Cloudflare IP addresses. The two most common causes of 521 errors are:

Error 522 occurs when Cloudflare times out contacting the origin web server. Two different timeouts cause HTTP error 522 depending on when they occur between Cloudflare and the origin web server:

This error occurs when Cloudflare cannot contact your origin web server. This typically occurs when a network device between Cloudflare and the origin web server does not have a route to the origin's IP address.

Error 524 indicates that Cloudflare successfully connected to the origin web server, but the origin did not provide an HTTP response before the default 125 seconds Proxy Read Timeout. This can happen if the origin server is taking too long because it has too much work to do, for example, a large data query, or because the server is struggling for resources and cannot return any data in time. The error 524 occurs if the origin web server acknowledges (ACK) the resource request after the connection has been established, but does not send a timely response (within the Proxy Read Timeout delay, 125 seconds by default).

This error indicates that the SSL handshake between Cloudflare and the origin web server failed. Error 525 occurs when these two conditions are true:

This error indicates that Cloudflare is unable to verify the SSL certificate on your origin server, preventing a secure connection from being established. This error occurs when these two conditions are true:

This error indicates that Cloudflare is unable to resolve the origin hostname, preventing it from establishing a connection to the origin server. An HTTP error 530 is returned when Cloudflare is encountering an issue resolving the origin hostname. In this case the body of the response contains an 1XXX error code.

This error indicates that a Cloudflare DNS record points to a prohibited IP, blocking access to the requested domain. Cloudflare halted the request for one of the following reasons:

This error indicates a DNS resolution failure preventing access to the requested domain. - A web request was sent to a Cloudflare IP address for a non-existent Cloudflare domain. - An external domain that is not on using Cloudflare has a CNAME record to a domain active on Cloudflare - The target of the DNS CNAME record does not resolve. - A CNAME record in your Cloudflare DNS app requires resolution via a DNS provider that is currently offline.

This error indicates that a Cloudflare DNS record points to a prohibited IP, preventing proper domain resolution. - A DNS record in your Cloudflare DNS app points to one of Cloudflare's IP addresses. - An incorrect target is specified for a CNAME record in your Cloudflare DNS app. - Your domain is not on Cloudflare but has a CNAME that refers to a Cloudflare domain.

This error indicates that direct access to a Cloudflare IP address is not allowed. A client or browser directly accesses a Cloudflare IP address.

This error indicates that the host is not configured to serve web traffic. - Cloudflare staff disabled proxying for the domain due to abuse or terms of service violations. - DNS changes have not yet propagated or the site owner's DNS A records point to Cloudflare IP addresses.

This error indicates that access to the website is denied due to the banning of the Autonomous System Number (ASN). The owner of the website (for example, example.com) has banned the autonomous system number (ASN) from accessing the website.

This error indicates that access is denied because your IP address has been banned. A Cloudflare customer blocked traffic from your client or browser.

This error indicates that access is denied because your IP address has been banned. A Cloudflare customer blocked traffic from your client or browser.

This error indicates that access is denied because your IP address has been banned. A Cloudflare customer blocked traffic from your client or browser.

This error indicates that access to the website is denied from your country or region. The owner of the website (for example, example.com) has banned the country or region your IP address from accessing the website.

This error indicates that access to the website is denied based on your browser's signature. - A website owner blocked your request based on your client's web browser. - The request was sent to a *.pages.dev or *.workers.dev hostname, or to a custom domain of a Pages project, with a User-Agent header that Browser Integrity Check treats as a non-browser client (for example, the default Python urllib user agent). Refer to Requests to Pages projects or workers.dev.

This error indicates that access to the resource is denied due to hotlinking protection. A request is made for a resource that uses Cloudflare hotlink protection.

This error indicates that access to the website is denied. A website owner forbids access based on malicious activity detected from the visitor's computer or network (ip_address). The most likely cause is a virus or malware infection on the visitor's computer.

This error indicates a mismatch between the HTTP hostname and the TLS SNI hostname. The hostname sent by the client or browser via Server Name Indication (SNI) does not match the request host header.

This error indicates that a CNAME record between domains in different Cloudflare accounts is prohibited. Common causes include:

The website you are trying to visit has received too many requests and has temporarily blocked you from accessing it. The website owner has configured rate limiting rules that restrict how many requests a visitor can make to their site in a given time period. When you exceed this limit, Cloudflare returns a 1015 error.

This error indicates that Cloudflare cannot resolve the origin web server's IP address. Common causes for error 1016 are:

This error indicates that the host could not be found. - The Cloudflare domain was recently activated and there is a delay propagating the domain's settings to the Cloudflare edge network. - The Cloudflare domain was created via a Cloudflare partner (for example, a hosting provider) and the provider's DNS failed.

This error indicates a compute server error related to a Cloudflare Worker. A Cloudflare Worker script recursively references itself.

This error indicates that a Cloudflare security feature configured by the website owner blocked the request. Cloudflare returns it with an HTTP 403 status code. A security rule with a _Block_ action matched the request, and the rule has no custom response configured. For example, API Shield schema validation and JWT validation can block requests with a 1020 error.

This error indicates that the host could not be found due to a configuration issue or propagation delay. - If the owner just signed up for Cloudflare it can take a few minutes for the website's information to be distributed to our global network. Something is wrong with the site's configuration. - Usually, this happens when accounts have been signed up with a partner organization (for example, hosting provider) and the provider's DNS fails.

This error indicates that the domain has reached its plan limits for Cloudflare Workers. A request is not serviced because the domain has reached plan limits for Cloudflare Workers.

This error indicates an issue with Cloudflare Tunnel. You have requested a page on a website (tunnel.example.com) that is on the Cloudflare network. The host (tunnel.example.com) is configured with Cloudflare Tunnel, and Cloudflare is currently unable to resolve it.

This error indicates that the IP address used for the domain is restricted by Cloudflare's edge validation. Edge IP Validation (EIV) is a safeguard for restricted IP space that is meant to be used by specific Cloudflare accounts, such as BYOIP prefixes, dedicated/static IP allocations, or other customer-associated IP ranges. When EIV is enabled, Cloudflare checks whether incoming traffic to those IPs is associated with an authorized account before allowing the request to proceed. This helps prevent accidental misrouting or unauthorized use of dedicated IP space while keeping properly configured traffic flowing normally.

This error indicates an invalid URI path in a request rewrite. The value or expression of your rewritten URI path is not valid.

This error indicates that the rewritten URI path or query string exceeds the maximum allowed length. The value or expression of your rewritten URI path or query string is too long.

This error indicates that the rewrite rule expression could not be evaluated. There are several causes for this error, but it can mean that one expression element contained an undefined value when it was evaluated.