All Tools

Find out if anyone can send email pretending to be your domain — a plain-language SPF and DMARC verdict in seconds, no signup.

Find out if your domain has email problems and what to fix — SPF, DKIM, DMARC, MX, and delegation in one report.

See which mail servers receive email for your domain — and whether they're configured correctly.

Check whether the right mail servers are allowed to send as your domain — and whether your SPF record has hit the DNS lookup limit.

Check whether your email signing keys are healthy and strong enough to keep spammers from forging your domain.

Find out if spammers can fake email from your domain — and what to do about it.

See who's sending email as your domain. Drop in a DMARC XML report from your provider — sources, pass/fail rates, alignment. Nothing leaves your browser.

Check whether your domain enforces TLS for inbound email — modern receivers prefer it, and missing it can hurt deliverability.

Check whether your mail server is on a spam blacklist — being listed is a common reason legitimate email lands in spam.

Paste an email's headers to see exactly how it traveled — and where authentication failed if it landed in spam.

Send a real email and see how it authenticated — SPF for the address that actually connected, every DKIM signature, and whether either aligned with your From address.

Build a working SPF record for your domain — list your mail providers, see the DNS lookup cost, copy the result.

Build a working DMARC record for your domain — pick how strict, where reports go, copy the result.

Test whether your mail server accepts SMTP connections, supports STARTTLS, and has valid TLS certificates — ports 25, 465, and 587.

See all DNS records for a domain in one shot — A, AAAA, CNAME, MX, NS, TXT, and SOA.

Reverse DNS — find the hostname an IP address claims. Mail servers check this; missing or mismatched PTR hurts deliverability.

Check whether your domain is signed with DNSSEC and the signature chain back to the root is intact.

Find out when a domain expires — useful before you lose it (or to gauge how long a domain has been registered).

Check whether your domain's nameservers agree with each other and with the parent zone — the kind of silent issue that breaks email.

Test whether a host is reachable and how fast it responds.

Trace the network path between us and a host — see where traffic slows or stalls.

Show the public IP address your traffic appears to come from.

Look up the country, region, ISP, and ASN for an IP address.