Free · Two checks · Plain English
Find out why your emails go to spam, in two minutes.
Step one reads your domain's SPF, DKIM and DMARC records. Step two hands you a one-time address: send it an email and see whether your real mail passes the checks Gmail and Outlook run.
Step 1
Check the records
What the public DNS says about who may send as you, whether messages are signed, and what receivers should do when they're not.
Step 2
Send a test email
Get a one-time address, send it any email from the account you're worried about, and see the real verdicts within a minute.
The three records
What each one does, in one line.
SPF
A list of the servers allowed to send mail from your domain. Missing or wrong, and anyone can pretend to be you, and receivers know it.
DKIM
A signature on each message proving it came from your domain's key and wasn't altered. Set up once in your mail provider.
DMARC
The policy that ties the two together: what receivers should do when a message fails, and reports back to you about who's sending as you.
Since 2024, Gmail and Yahoo require all three for anyone sending in volume and weigh them for everyone else. Google: Email sender guidelines · checked Oct 2026
Fix it
Most fixes take 20 minutes.
Fix SPF
One TXT record listing every service that sends for you. The generator counts lookups so it doesn't break.
Turn on DKIM
A switch in Google Workspace, Microsoft 365, Zoho or your newsletter tool, plus one DNS record they give you.
Add DMARC
One TXT record named _dmarc, starting with p=none to monitor, then quarantine, then reject.
Google Workspace guide Microsoft 365 guide Wix guide GoDaddy guide
Why the test email
Records can look right and still fail.
A DNS check tells you what you published. The test email tells you what your mail provider actually did: which server it sent from, whether it signed the message with your domain's key or its own, and whether the result lines up with the address people see. That alignment is what DMARC judges, and it's where most "but my records are fine" cases fail.
One-time address
Unique to your test; expires after use.
Reads the headers only
The message body is discarded; only pass/fail and the sending domain are kept.
Plain verdicts
"DKIM passed, but for mailchimp.com, not your domain" is the kind of thing it says.
Questions
Why do my emails go to spam?
Usually one of three things: your domain's authentication records (SPF, DKIM, DMARC) are missing or wrong; a tool sends on your behalf without being authorised; or the content and sending pattern look like bulk mail. This page checks the first two in a minute; the fix guides cover the third.
What's the difference between the DNS check and the test email?
The DNS check reads your public records. The test email shows what actually happens when you send: which server sent it, whether it was signed, and whether the checks Gmail and Outlook run passed. The test email is the one that can't be fooled.
Do you keep the test email?
No. The service that receives it reads the authentication headers, stores the pass/fail results and the sending address, and discards the message. Results are kept 30 days.
I fixed the records. How long until it works?
DNS changes are usually visible within minutes, sometimes a few hours. Send another test email to confirm.
Everything passes but mail still lands in spam
Then it's reputation or content: a new domain, a sudden volume jump, spam-trigger wording, link shorteners, or past complaints. Warm up slowly, send to people who asked, and keep a plain-text version of every email.
Ari Rosenberg, Consult With Ari