Free SPF, DKIM & DMARC Checker
Verify your domain email authentication in one click. See which records pass, which fail, and how to fix them.
How it works
Enter your domain name
Just the domain. We handle the DNS lookups automatically.
We query live DNS records
SPF, DKIM (across 10+ common selectors), and DMARC records checked in parallel.
Get pass/fail for each record
See the raw record, whether it passes, and what to fix if it doesn't.
Why this matters
SPF, DKIM, and DMARC are the three pillars of email authentication. Without them, email providers are more likely to mark your messages as spam. Most cold email deliverability problems start with misconfigured authentication records.
Keep your records healthy
DNS records break silently. SendKit watches your SPF, DKIM, and DMARC across every domain and alerts you before deliverability drops.
Continuous monitoring
Get alerted if any auth record changes or breaks
DKIM rotation alerts
Know when your DKIM keys need rotating before they expire
Full DNS audit
MX, A, CNAME, and TXT record analysis across all your domains
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Got questions? We've got answers.
SPF (Sender Policy Framework) is a DNS record that lists which servers are authorized to send email from your domain. It prevents spammers from spoofing your domain.
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