SPF, DKIM & DMARC Checker

What these records do

• SPF - lists which mail servers are authorized to send email for the domain. Receiving servers check the sending server's IP against this list.
• DKIM - a cryptographic signature added to outgoing mail, letting the receiving server verify the message wasn't altered in transit and genuinely came from an authorized sender.
• DMARC - tells receiving servers what to do when SPF or DKIM checks fail (ignore, quarantine, or reject), and where to send reports about it.

Why DKIM needs a selector

Unlike SPF and DMARC, which always live at a fixed, predictable location, a DKIM record's location depends on a "selector" chosen by whoever configured mail for that domain - there's no DNS record that reveals what it is. If you know your provider's selector, enter it above. Otherwise we try selectors commonly used by default by major providers (Google Workspace, Microsoft 365, Mailchimp, SendGrid, and others) - finding nothing doesn't necessarily mean DKIM isn't configured, just that it's not using one of those.

Read more: SPF, DKIM, DMARC: Email Authentication Explained Simply.