SPF
SPF lists the servers allowed to send mail for your domain. A missing or broken record makes receivers more suspicious of form notifications sent From that domain.
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Contact form deliverability diagnostic
If your contact form submits but the email never arrives, check the recipient address first, then the spam folder, then your sender configuration, then the form backend log. This diagnostic sends you to the SPF, DKIM and DMARC checkers for the domain in your From address and explains what each result means.
Paste the domain from the From address into each checker, then use the notes below to read each result.
DKIM
DKIM adds a cryptographic signature that receivers can verify, and it usually survives forwarding. You need the selector your email provider uses as well as the domain.
DMARC
DMARC tells receivers what to do when SPF or DKIM fails, and it sends you reports. Start with a monitoring policy before you move to quarantine or reject.
These checkers read public DNS records. Passing DNS checks helps receivers trust your mail, but it does not guarantee inbox placement: reputation, content, recipient filters and sending volume still matter.
What each check tells you
SPF tells receivers which servers may send mail for your domain. If the domain in your From address has no SPF record, or the record does not include the server that sends your form notifications, receivers have less reason to trust the message.
DKIM gives each message a cryptographic signature that the receiver can verify against a public key in DNS. A correct signature also survives many forwarding paths, where SPF can break.
DMARC ties SPF and DKIM to the From domain and tells receivers what to do when neither passes. A monitoring policy with reporting shows you which senders are failing before you tighten it.
These are public DNS records, so the checkers can only show what is published. They cannot see your inbox, your form backend or your sender reputation. Use them as evidence about the sender configuration, then keep working through the sequence below. For the full setup order and the alignment mistakes that cause failures, read the email authentication guide for form notifications.
Troubleshooting sequence when a form email is missing
- Check the recipient address. Open the form backend settings and read the destination address character by character. Look for a typo, an old employee address, or an address that still needs verification. Send a test to a mailbox you control to prove the path works.
- Check the spam folder and quarantine. Search all mail, including spam and promotions, for the subject line or the sender. On a work account, ask the admin to check the quarantine, because held messages do not appear in any normal folder.
- Check the sender configuration. Send From an address on a domain you control, put the visitor's address in Reply-To, and run the SPF, DKIM and DMARC checkers for the From domain. If the records are missing or do not cover the sending server, fix the sender side before changing anything else.
- Check the form backend logs. Find the entry for the test submission. Delivered means the problem is inbox-side. Bounced or rejected means the log should show an SMTP code. No entry means the send was never attempted, so look for a swallowed error or a quota cutoff.
FAQ
Why does my contact form say it sent but no email arrives?
A success message only confirms the browser reached the form backend. The notification email is a separate step after that, so the missing message is usually a wrong recipient address, a spam or quarantine folder, a sender authentication problem, or an error recorded in the form backend log. Work through those four checks in that order.
Does passing SPF, DKIM and DMARC guarantee inbox delivery?
No. The records help receivers verify that your sending server is allowed to use your domain, and they reduce spoofing risk, but inbox placement also depends on sender reputation, message content, recipient filters and sending volume. Treat the DNS checks as one part of the diagnosis, not a guarantee.
How do I find the domain to check for SPF, DKIM and DMARC?
Look at the From address on the notification your form sends, then use the part after the @ sign. If your form sends From hello@yourdomain.com, check yourdomain.com. For DKIM you also need the selector from your email provider, which appears as the s= value in a message's DKIM-Signature header.
What should I check after the DNS records look correct?
Check the recipient address in your form backend settings for a typo or an unverified destination, search all mail plus spam and quarantine, confirm the sender configuration uses an address on your authenticated domain, and read the backend log to see whether the send was delivered, bounced or never attempted.
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