Free tool
Is your email set up right?
Check a domain's SPF, DKIM and DMARC records, MTA-STS and TLS reporting in one go, with what to fix and the exact record to add.
Checked from Stockholm, Sweden · Free, no sign-up
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Questions
What do SPF, DKIM and DMARC do?
SPF lists the servers allowed to send mail for your domain. DKIM signs each message so receivers can tell it wasn't changed. DMARC tells receivers what to do with mail that fails both, and where to send reports.
Is p=none enough?
p=none only collects reports: mail that pretends to be from you is still delivered. Start there, read the reports for a few weeks, then move to p=quarantine and p=reject once your own senders pass.
Why can't the checker find my DKIM key?
DKIM keys live under a selector name only your mail provider knows, such as google._domainkey. We try your provider's selectors and the common ones; add yours in the field if it's different.
Do Gmail and Yahoo require DMARC?
Since 2024, anyone sending more than 5,000 messages a day to Gmail or Yahoo addresses needs SPF, DKIM and a DMARC record. Smaller senders need SPF or DKIM, and mail without them increasingly lands in spam.
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