Free email security checker
Check a domain's SPF, DKIM and DMARC records: the settings that stop criminals sending email that looks like it came from you.
What it checks
MX
Where mail for the domain is delivered, or whether it accepts mail at all.
SPF
One record only, how it ends (-all, ~all, ?all or +all), and how many DNS lookups it uses.
DMARC
The policy (none, quarantine or reject), how much mail it covers, subdomains, and whether reports are sent.
DKIM
Signing keys on the selectors Microsoft 365, Google Workspace and other common providers use.
Questions
What are SPF, DKIM and DMARC?
SPF lists the servers allowed to send mail for your domain. DKIM signs each message so receivers can tell it was not changed. DMARC tells receivers what to do with mail that fails, and sends you reports.
Which DMARC policy should I use?
Start with p=none and a reporting address while you confirm all your own mail passes, then move to p=quarantine and finally p=reject, which blocks spoofed mail.
Why is DKIM not found?
The checker tries common selector names. If your provider uses a different one, ask them or look at the DKIM settings in your email admin console.
Is anything stored?
No. The domain you enter is looked up and the answer is shown to you; the checker does not save or log it.
Also free: Free SSL certificate checker · Free website security headers checker · Free DNS lookup · All free tools
Check every customer, every day
TechSavve RMM checks websites, DNS, mail and certificates for every customer directly from the platform, alongside agentless monitoring of their devices.