Free Domain & DNS tools
Every website and mailbox depends on DNS being right. Look up the records a domain publishes, see whether a change has spread worldwide, and check who owns a domain and how long it has been registered.
8 tools · free to use
Domain & DNS tools
DNS Lookup & Health Check
Look up every DNS record for a domain — A, AAAA, NS, MX, TXT, SOA, CAA — and check nameserver redundancy, CAA and DNSSEC in one place.
Open CheckerDNS Propagation Checker
Check DNS propagation across public resolvers worldwide. Compare A, AAAA, MX, TXT, NS and CNAME answers and see how long caches have left.
Open New CheckerWHOIS Lookup
Look up any domain's WHOIS record: registrar, IANA ID, abuse contact, creation and expiry dates, EPP status codes explained, nameservers, DNSSEC and raw RDAP data.
Open CheckerDomain Age Checker
Check how old a domain is, when it expires, who the registrar is and whether it is transfer-locked. Works for .com, .co.uk, .uk and 1,000+ extensions.
Open New ToolWhat Is My IP Address
See the public IP address websites see, IPv4 or IPv6, your network and browser details, and look up any IP for reverse DNS and registered owner.
Open New ToolSubnet Calculator
Free IPv4 and IPv6 subnet calculator: network, broadcast, host range, masks, address type and reverse DNS. Split, VLSM, summarize routes and export to CSV.
Open New CheckerSubdomain Finder
Find a domain's subdomains from public certificate logs, see which resolve, and spot dangling CNAMEs that risk subdomain takeover and exposed staging sites.
Open CheckerMX Lookup
MX lookup and email host finder: see which provider hosts email for a domain, its mail servers, priorities, IPs and reverse DNS, and any security gateway.
Also in Email & deliverability OpenFree website audit
See how your site scores, free
Speed, SEO, DNS, email (SPF/DKIM/DMARC) and security in one scan, with a prioritised fix list.