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SPF, DKIM and DMARC checker
Enter a domain: the tool reads its DNS and tells you what is missing for your prospecting emails to reach the inbox.
The check runs in your browser, against a public DNS resolver. Nothing goes through our servers.
What does this tool check?
Four DNS records that mailbox providers read before deciding where your email goes:
- MX: can the domain receive? Without it, neither replies nor bounces arrive.
- SPF: the list of servers allowed to send for the domain. One record only, ending in -all or ~all.
- DKIM: the signature proving the message was not altered. The tool tries the most common selectors.
- DMARC: what the provider should do with a message that fails, and where to send reports.
Everything is green and my emails still go to spam: why?
Because authentication is a condition, not a guarantee. On our side, perfectly configured domains went to spam at Gmail and reached the inbox at Outlook: it was the reputation of the sending address, not the setup. We tell that story in why your cold emails go to spam in Gmail.
Why is "not found" for DKIM not an error?
A DKIM key is published under a selector chosen by your provider, and DNS cannot list every selector. If no common selector answers, the tool says so without concluding: look at the s= field of the DKIM-Signature header of an email you sent.
Frequently asked questions
Does my data go through your servers?
No. The lookup runs from your browser against a public DNS resolver. We see neither the domain nor the result.
Should DMARC be set to p=reject?
Start with p=none and a reporting address, read the reports for a few weeks, then move to quarantine once every legitimate sender passes.
How many SPF records can a domain have?
One. Two SPF records make the check fail at mailbox providers.
Every day Romeo spots the companies that need you and writes the first message. Nothing leaves without your approval.
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