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Parameters

Custom error rules

Custom error rules define when a custom error gets triggered and the content that is served to visitors.

Rule parameters are the following:

  • asset_name String Optional
    • The name of the custom error asset you previously uploaded. The asset may include error tokens that will be replaced with real values before sending the error response to the visitor.
    • A custom error rule can only reference an asset defined in the same scope as the rule (that is, in the same zone or account).
    • You must provide either the asset_name or the content parameter.
  • content String Optional
    • The response body to return. It can include error tokens that will be replaced with real values before sending the error response to the visitor.
    • You must provide either the asset_name or the content parameter.
    • The maximum content size is 10 KB.
  • content_type String Required
    • The content type of the returned response. Must be one of the following:
      • text/html
      • text/plain
      • application/json
      • text/xml
  • status_code Integer Optional
    • The HTTP status code of the response. If provided, this value will override the current response status code.
    • The status code must be between 400 and 999.

Custom error assets

A custom error asset corresponds to a web resource such as an HTML web page (including any referenced images, CSS, and JavaScript code) that Cloudflare fetches and saves based on a URL you provide, to be served to visitors as an error page.

Custom error assets have the following parameters:

  • name String Required
    • The name of the custom error asset.
    • Example value: "500_error_template".
    • An asset name can contain the following characters:
      • Uppercase and lowercase letters (A-Z and a-z)
      • Numbers (0-9)
      • The underscore (_) character
    • The maximum length is 200 characters.
  • description String Optional
    • A string describing the custom error asset.
    • Example value: "Standard 5xx error template page".
  • url String Required
    • The URL of the page you want Cloudflare to fetch and store, to be served later to visitors as error pages according to the configured custom error rules.
    • Example value: "https://example.com/errors/500.html".
    • When you create or update an asset and provide a URL, Cloudflare collects any images, CSS, and JavaScript code used in the page, minifies the content, and saves it internally.
    • The content of the page at the specified URL may include error tokens that will be replaced with real values before sending the error response to the visitor.
    • If you update an asset and provide the same URL, Cloudflare will fetch the URL again, along with its resources, and store it internally.
    • The maximum asset size is 1.5 MB.