SPF
Sender authorization problems and policy fixes.
SPF, DKIM & DMARC Checker for Email Deliverability
Emails landing in spam or failing authentication usually trace back to SPF, DKIM, or DMARC misconfigurations.
This free checker performs a live DNS lookup and shows whether your domain publishes valid authentication records. In seconds you can spot missing records, weak policies, and common configuration mistakes that hurt inbox placement.
No login required. Live DNS only. Built for fast email authentication triage.
SPF
Verifies which servers may send email for your domain.
DKIM
Cryptographically signs messages to protect integrity.
DMARC
Defines what happens when authentication fails.
Common SPF, DKIM and DMARC problems
These are the most common authentication issues we see when diagnosing email deliverability problems. Each guide includes practical fixes, DNS examples, and related troubleshooting paths.
DKIM
Signing, selector, and key-related issues.
DMARC
Policy, alignment, and reporting issues.
How email authentication works
Modern email authentication relies on three protocols working together. SPF tells receiving servers which infrastructure is allowed to send mail for your domain. DKIM adds a cryptographic signature so receivers can verify that the message was not altered in transit. DMARC builds on top of SPF and DKIM by defining policy and alignment rules for messages that fail checks.
When these records are configured correctly, mailbox providers can trust your email more easily. When they are missing or broken, legitimate messages often lose trust and drift toward spam.
Why teams use this checker
- Live DNS lookup
- No login required
- Instant SPF, DKIM, DMARC diagnostics
- Clear troubleshooting guidance
Check SPF, DKIM and DMARC records
Email authentication is critical for modern email deliverability. Mail providers like Gmail, Microsoft and Yahoo expect domains to publish SPF, DKIM and DMARC records so they can verify that email messages are legitimate.
This tool checks all three protocols using live DNS lookups and helps you quickly identify missing records, misconfigurations and alignment problems that may cause emails to land in spam.
Start with the checker above, then use the protocol hubs for deeper troubleshooting and copy-paste record examples.