Free tools
15 checks you can run right now
Every tool here runs the same engine the paid monitor runs, against live DNS. The free answer and the monitored answer can never disagree, because there is only one of them.
- Tools
- 15
- Cost
- $0
- Sign-up
- None
The bench
01SPF LookupResolve and validate an SPF record, including the 10-lookup limit.→02DKIM LookupFind and inspect DKIM public keys on any selector.→03DMARC LookupRead a DMARC policy and judge how much it actually protects.→04MX LookupList mail exchangers with priorities and resolved addresses.→05BIMI LookupCheck a BIMI record and whether its logo and VMC qualify.→06PTR LookupReverse-resolve a sending IP and check forward-confirmed rDNS.→07MTA-STS CheckerFetch the policy file and verify enforcement mode and MX match.→08Mail Provider LookupIdentify who actually handles mail for a domain.→09Blacklist CheckerQuery 34 DNSBLs for a domain or IP in one pass.→10DMARC GeneratorBuild a DMARC record with a policy you can defend.→11SPF GeneratorCompose an SPF record that stays under the lookup limit.→12Subject Line TesterScore a subject line for spam triggers and clarity.→13Email Headers AnalyzerTrace a message hop by hop and read its auth results.→14WHOIS LookupRegistration, registrar and nameservers via WHOIS/RDAP.→15Domain Health CheckThe full scan — every check the paid monitor runs, once.→
Every tool runs live against public DNS — 41 checks in the full scanSame engine as the monitor
Or run all 41 at once.
One domain, one pass, every check — with each finding diagnosed and paired with its exact fix.