About Domain Check Desk

Last updated 2026-10-13

Domain Check Desk is a free set of tools for people who look after domains: site owners, IT admins, email senders and developers. Each page does one job and works straight away: there is no account and nothing to install.

What you can check here

DNS records: every common record type, A/AAAA, MX, TXT, CNAME, NS, PTR (reverse DNS) and CAA, from two public resolvers.
Email records: SPF (with the 10-lookup count), DKIM by selector and DMARC policies.
Propagation and DNSSEC: how several large public resolvers answer right now, and whether a domain is signed and validates.
Registration: registrar, dates and status from the registry’s RDAP service, and domain expiry dates.
Certificates: what a site’s HTTPS setup shows, the certificates logged for it in Certificate Transparency, and decoders for certificates and CSRs that work entirely offline in your browser.
Security headers and cookies: HSTS, Content Security Policy, frame protection, cookie attributes, with generators for CSP and Set-Cookie lines.

How the checks work

DNS answers come from public DNS-over-HTTPS resolvers (Cloudflare DNS and Google Public DNS, plus a few others on the propagation page), registration data from RDAP, the registries’ official lookup protocol, and certificate history from public Certificate Transparency logs (crt.sh). Your browser asks these services directly. Header and HTTPS checks go through a small read-only check service on this site, described on each page that uses it. Every rule the tools apply names the standard it comes from (the RFC or specification) on the page.

How it works

Your browser does the work. Decoders and generators never send what you paste anywhere. Live checks send only the domain or address you enter, to the services named above.
Results are computed, not typed in. The examples on each page are produced by the same code the tool runs, and the code is tested against independently calculated results.
Third-party material used on the site is listed on the credits page.

If a tool gives a wrong result, please tell us through the contact page.

Who runs it

Domain Check Desk is owned and operated by the Domain Check Desk team. You can write to us at support@360jiance.com.

Advertising

The site is free to use. We may show advertising in future to pay for hosting and development. If we do, ads will be labelled “Advertisement”, will never cover a tool, and are described in the privacy policy.