Email deliverability checker
Enter your domain to see its SPF, DMARC and MX records. Each check gets a pass, warning or fail result and a one-line fix, so you know exactly which DNS record to add when your form emails land in spam or never arrive.
FAQ
What does this email deliverability checker look up?
Three public DNS records for the domain you enter: the SPF record (a TXT record starting with v=spf1), the DMARC record (a TXT record at _dmarc.yourdomain.com starting with v=DMARC1) and the MX records that say which servers receive your mail. Nothing else is queried.
Why do my contact form emails go to spam?
Usually because the From address uses a domain that hasn't authorized the server sending the mail. Publish SPF and DKIM for the domain you send from, add a DMARC record, and send the From address on that domain with the visitor's email in Reply-To.
What is the SPF 10 lookup limit?
SPF allows at most 10 DNS lookups while a receiver checks your record. Each include:, a, mx and redirect= term counts, and includes can add more of their own. Over 10, receivers return a permanent error and treat SPF as failed. This tool counts the terms in your top-level record as an estimate.
Which DMARC policy should I start with?
Start with p=none and a rua= address so you receive reports without blocking anything. When the reports show your real senders passing SPF or DKIM, move to p=quarantine and then p=reject.
Does this check DKIM?
Not on this page. A DKIM key lives at <selector>._domainkey.yourdomain.com, and your email provider picks the selector. Use the free DKIM record checker at /tools/dkim-checker: it has selector presets for Google Workspace, Microsoft 365 and other common senders.
All free form tools · Why form emails go to spam · Send form emails from your own domain
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Terms explained in the form glossary: SPF, DKIM, DMARC, SMTP, Transactional email