Free tools
Every email health check, in one place
No account, no card, no email wall on the basic result. Run any check below in about ten seconds.
Pick a check
Start with whichever question you actually have
Not sure where to start? DMARC is the one most domains have never checked.
DMARC Checker
freeSee whether spoofed email pretending to be your domain gets blocked, quarantined, or waved through.
Run this check →SPF Checker
freeCount your SPF DNS lookups against the hard 10-lookup limit, with a full breakdown of every include.
Run this check →DKIM Checker
freeFind active DKIM signing keys by probing common selectors, or check one you already know.
Run this check →MX Lookup
freeSee every mail server a domain is configured to receive email at, in priority order.
Run this check →Blacklist Checker
freeCheck your mail servers against 5 major spam blacklists (DNSBLs) at once.
Run this check →Email Header Analyzer
freePaste raw email headers, get a plain-English breakdown of the SPF/DKIM/DMARC verdicts and delivery path.
Run this check →Compliance Checker
freeCheck the DNS-verifiable parts of Gmail and Yahoo's 2024 bulk-sender rules.
Run this check →SPF Generator
freeBuild a correctly formatted SPF record for any combination of email providers.
Run this check →SPF Flattener
freeResolve SPF includes down to literal IPs to fix a record over the 10-lookup limit.
Run this check →DMARC Generator
freeBuild a DMARC record with a guided policy from none to quarantine to reject.
Run this check →DKIM Generator
freeGenerate an RSA key pair entirely in your browser — your private key never leaves your device.
Run this check →Deliverability / Inbox Test
soonSend a test email and get a graded report on where it landed.
These checks run once. Monitoring never stops.
Every tool above gives you a snapshot. Turn on free monitoring for your first domain and we'll watch it every day, then tell you the moment something changes.
See monitoring plans