Make API requests to 1.1.1.1 over DoH
Cloudflare offers a DNS over HTTPS resolver at:
https://cloudflare-dns.com/dns-query
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-udpwireformat
) 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 1.1.1.1, but rather how DoH works.
You can learn more about how DoH works in RFC8484, more specifically the HTTP layer requirements.
Example request:
$ curl --http2 -H "accept: application/dns-json" "https://1.1.1.1/dns-query?name=cloudflare.com" --next --http2 -H "accept: application/dns-json" "https://1.1.1.1/dns-query?name=example.com"
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 Status | Meaning |
---|---|
400 | DNS query not specified or too small. |
413 | DNS query is larger than maximum allowed DNS message size. |
415 | Unsupported content type. |
504 | Resolver timeout while waiting for the query response. |