Firefox Canary domain. If it returns an IP, DoH will be used

use-application-dns.net

Public list of DoH servers.

Official documentation Interactive web page here. Add -v for verbose mode.

curl -H "accept: application/dns-json" "https://dns.google/resolve?name=www.google.com&type=A"

Note: There is also a human-friendly web interface at https://dns.google/. This web app displays JSON results in a browser but does not implement an API; do not confuse its https://dns.google/query? URLs with the two API URLs. It will return the following

{"Status":0,"TC":false,"RD":true,"RA":true,"AD":false,"CD":false,"Question":[{"name":"www.google.com.","type":1}],"Answer":[{"name":"www.google.com.","type":1,"TTL":128,"data":"172.217.16.228"}]}

Which breaks out to

{
    "Status":0,
    "TC":false,
    "RD":true,
    "RA":true,
    "AD":false,
    "CD":false,
    "Question":
    [
        {
            "name":"www.google.com.",
            "type":1
        }
    ],
    "Answer":
    [
        {
            "name":"www.google.com.",
            "type":1,
            "TTL":128,
            "data":"172.217.16.228"
        }
    ]
}

Add -v for verbose mode.

curl -H "accept: application/dns-json" "https://cloudflare-dns.com/dns-query?name=www.google.com&type=A"

Response is the same as for Google (above) but doesn't have the extra . at the end of the domains.

curl -H "accept: application/dns-json" "https://dns.quad9.net/dns-query?name=www.google.com&type=A"

Following RFC, the endpoint should receive a base64 encoded HTTP friendly DNS packed.

https://f11a1d22-ebec-2222-1111-52992759684b.doh.threatdefense.infoblox.com/dns-query?dns=AAABAAABAAAAAAAAA3d3dwdleGFtcGxlA2NvbQAAAQAB

Test with dog

dog lookup.dog -H @https://f11a1d22-ebec-2222-1111-52992759684b.doh.threatdefense.infoblox.com/dns-query