SPF/DKIM/DMARC diagnostics

SPF, DKIM and DMARC are three records in your domain's settings that prove an email really comes from you. SPF lists the servers allowed to send for your domain, DKIM adds a digital signature to each message, and DMARC tells receiving servers what to do when a message fails either check. DNS diagnostics is a tool feature that reads these records, tests them and reports mistakes in plain terms. Folderly, Lemwarm, MailReach and Warmy.io are examples of tools that offer it.

Mailbox providers increasingly expect these records, and bulk senders are required to have them in place. A missing or faulty record can send legitimate messages to spam or have them rejected, and the cause is hard to spot without a tool because the email simply fails to arrive. A diagnostic shows the problem and the fix.

You need it when you set up a new domain or change your email provider, and any time delivery suddenly drops. If your email platform guides you through setup and checks the records itself, you may not need a separate tool.

The records are only changed in your domain settings, so you or your IT contact must still make the edits.

• Does it check all three records, and explain each problem in plain language.
• Does it check automatically on a schedule, or only when you press a button.
• Does it alert you when a record changes or breaks.
• Does it give the exact value to add, or only report that something is wrong.