Email domain health check
One scan of the five records that decide whether your email is trusted. Each result says what is wrong in plain English and what to change.
What this check covers
SPF lists the servers allowed to send as your domain. DKIM signs each message so receivers can tell it was not altered. DMARC tells receivers what to do when SPF and DKIM do not line up, and where to send reports. MX records say where your replies and bounces go. The HTTPS check covers the certificate on your website, which the links in your emails point to.
Since February 2024, Gmail and Yahoo require SPF, DKIM and a DMARC record from anyone who sends in bulk. Microsoft began enforcing similar rules for Outlook.com in May 2025.
Why a one-off check is not enough
These records break quietly. Someone adds a new email tool and its SPF include pushes you over the 10-lookup limit. A DNS migration drops the DKIM key. A registrar change wipes the DMARC record. Mail keeps sending, it just starts landing in spam. SenderBeacon re-runs this check twice a day and emails you when something changes or fails.
Monitor it instead of checking by hand
Watch this domain and get an email the day any of these break. Plans from $9/month after a 14-day free trial. No card to start.
Questions
Is this check free?
Yes. One-off checks are free and need no account. Continuous monitoring with alerts is a paid plan from $9 a month, with a 14-day free trial and no card required.
Do you send any email to my domain?
No. Every check is a read-only DNS lookup or an HTTPS handshake. Nothing is sent to your mailboxes.
Why does DKIM say "unknown"?
DNS cannot list DKIM selectors, so we try the selectors common providers use. If yours is custom, find "s=" in the DKIM-Signature header of an email you sent and enter it in the selector box.
More free checks
- SPF record checker
- SPF “too many DNS lookups” checker
- DMARC record checker
- DKIM record checker
- MX record lookup
- SSL certificate expiry checker
- SPF record generator
- DMARC record generator