SPF & DMARC Checker
Review the email authentication policies that tell receiving servers which senders to trust and what to do with messages that fail. Catch common mistakes before they hurt deliverability.
Run a check
Results
Results aren’t available yet
Results will appear here once SPF & DMARC Checker launches.
How to use SPF & DMARC Checker
- Enter the domain used in your From address.
- Run the check to fetch and parse the SPF and DMARC records.
- Work through any warnings, starting with errors that make a record invalid.
What it checks
- SPF record presence and syntax
- SPF mechanisms and the 10 DNS-lookup limit
- Multiple or conflicting SPF records
- DMARC record at _dmarc
- DMARC policy and reporting addresses
- Subdomain policy and alignment settings
Frequently asked questions
What is the SPF 10-lookup limit?
When evaluating SPF, receivers perform at most 10 DNS lookups for mechanisms such as include, a, mx, ptr and exists, plus redirect. Going over the limit causes a permanent error, which can make SPF fail for legitimate mail.
Which DMARC policy should I use?
Start with p=none and review aggregate reports until all legitimate senders pass. Then move to quarantine and finally reject to stop spoofed messages being delivered.
Can a domain have more than one SPF record?
No. A domain must publish at most one SPF record. Several SPF TXT records cause a permanent error, so combine them into one.