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Make API requests to over DoH

Cloudflare offers a DNS over HTTPS resolver at:

​​ HTTP method

Cloudflare’s DNS-over-HTTPS (DOH) endpoint supports POST and GET for UDP wireformat, and GET for JSON format.

When making requests using POST, the DNS query is included as the message body of the HTTP request, and the MIME type (application/dns-message) is sent in the Content-Type request header. Cloudflare will use the message body of the HTTP request as sent by the client, so the message body should not be encoded.

When making requests using GET, the DNS query is encoded into the URL. An additional URL parameter of ct should indicate the MIME type (see below).

​​ Valid MIME types

If you use JSON format, set application/dns-json URL parameter, and if you use DNS wireformat, use application/dns-message as either the URL parameter of ct or a Content-Type header for POST requests.

See also curl examples for UDP wireformat and JSON.

​​ Send multiple questions in a query

Sending more than one question when making requests depends on the HTTP version used, as each DNS query maps to exactly one HTTP request. HTTP/2 and HTTP/3 have multiplexing, and you can start multiple requests concurrently. HTTP/2 is, in fact, the minimum recommended version of HTTP for use with DNS over HTTPS (DoH). This is not specific to, but rather how DoH works.

You can learn more about how DoH works in RFC 8484, more specifically the HTTP layer requirements.

Example request:

$ curl --http2 -H "accept: application/dns-json" "" --next --http2 -H "accept: application/dns-json" ""

​​ Authentication

No authentication is required to send requests to this API.

​​ Supported TLS versions

Cloudflare’s DNS over HTTPS resolver supports TLS 1.2 and TLS 1.3.

​​ Return codes

HTTP StatusMeaning
400DNS query not specified or too small.
413DNS query is larger than maximum allowed DNS message size.
415Unsupported content type.
504Resolver timeout while waiting for the query response.