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Free ToolsDomain Health Checker

Domain Health Checker

Scan your SPF, DKIM, DMARC and MX setup in one shot and get an A–F deliverability score. A clean configuration is the difference between the inbox and the spam folder.

Email Deliverability

Domain Health Checker

Check your domain's SPF, DKIM, DMARC and MX setup in one go. A clean configuration is the difference between landing in the inbox and landing in spam.

Leave the selector blank and we'll try the most common ones automatically.

How it works

From domain to deliverability score in seconds

1

Enter your domain

Type the domain you send cold email from, no login, no agent to install. Add a DKIM selector if you know it.

2

We scan your DNS live

We query SPF, DKIM, DMARC and MX records straight from public DNS, right in your browser.

3

Get a score + fixes

See an A–F grade with a plain-English verdict on every record and exactly what to fix first.

Keep going

More free tools

SPF Record CheckerLook up and validate the SPF record that authorizes who can send as you. DMARC Record CheckerCheck whether your domain publishes a DMARC policy against spoofing. DKIM Record CheckerValidate your DKIM key so your mail can be cryptographically signed.
Browse all free tools
FAQ

Common questions

What does the deliverability score mean?
It's a weighted grade across the four records inbox providers check most: SPF, DKIM, DMARC and MX. A higher score means providers can verify your mail is really from you, which keeps you out of spam.
Why is my domain failing DKIM when I send fine?
DKIM uses a provider-specific selector, and we can only guess the common ones. If you know your selector (e.g. google, selector1), enter it and re-run: a fail here is often just an unknown selector.
Do you store my domain or results?
No. The lookups run in your browser against public DNS and nothing is saved on our side.
My records look fine, why am I still landing in spam?
Authentication is necessary but not sufficient. Sending reputation, content, and mailbox warmup all matter too. That's the full job MailOptimal handles.
Stop fixing DNS by hand

Skip the DNS work entirely

MailOptimal sells pre-warmed Google, Microsoft and Azure mailboxes with SPF, DKIM and DMARC already configured, so every sender is inbox-ready on day one.

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