Trust beats tactics™

DNS

DNS Lookup

Enter a domain, a hostname or an IP address. We show you the records public DNS is giving out right now, and flag a few common problems that affect email.

New to DNS records? Read What are TXT, MX, CNAME, and A records? in the Email Almanac.

You can look up names like _dmarc.example.com or s1._domainkey.example.com too. An IP address runs as PTR.

How this tool works

What the lookup is actually doing

  1. 1

    It asks public DNS

    The lookup runs on our server against public resolvers. So it shows what public resolvers are giving out, not what your own laptop has saved.

  2. 2

    It pulls the record types email uses

    Choose one type, or leave it on all email records. You can also look up names like _dmarc.yourdomain.com or s1._domainkey.yourdomain.com. Enter an IP address and it runs a PTR lookup.

  3. 3

    It flags a few common problems

    It warns you when a domain has no MX record, when more than one SPF or DMARC record answers at the same name, and when an IP address has no PTR. For a deeper read, use our SPF and DMARC checkers.

The records that do the work for email

TXT
Plain text. Carries SPF, DKIM keys and DMARC.
MX
Which servers accept mail for the domain.
CNAME
An alias from one name to another.
A
Maps a hostname to an IPv4 address.
PTR
Maps an IP address back to a hostname.

When to use it

Reach for it in these moments

  • You changed a record and it still looks old

    Resolvers keep serving the cached answer until the old TTL runs out. Seeing the old value here usually means you need to wait, not that your change failed.

  • Mail to your domain is bouncing

    A missing or wrong MX record is the first thing to rule out, and this shows it.

  • A new tool asked you to add a TXT record

    Pull every TXT record at the name and look for a second SPF record or old verification strings from vendors you no longer use.

  • You are checking a sending IP

    Receiving servers look up the PTR of the connecting IP, and a missing or generic one counts against you.

Email Almanac

  • Not sure what this means?

    Ask a real person. The Email SOS Hotline is free help with any email problem, no pitch. Cleaning a list does not fix a DNS record, so if this check found a problem, start here.

    Ask the Email SOS Hotline

  • Keep this result

    Send it to your inbox, to share with your team or compare after a fix.

    Run a check, then email it

  • Your setup is one half. Your list is the other.

    A record that passes proves the mail is yours. Mailbox providers also judge you on who you send to. Clean your first 1,000 addresses free.

    Clean your first 1,000 free