Look Up a Domain's SOA Record
The primary server, serial number and zone timings.
How to use it
- Enter the root domain, without www.
- Press Check.
- Note the serial number so you can compare after making a change.
The SOA record is a DNS zone's identity card: it names the primary server responsible for it, the administrator's address, a serial number that increases with each edit, and the timings governing how servers synchronise.
The serial number is the practically useful part. After any edit to your records it should increase. If you changed something and the serial hasn't moved, the change either wasn't saved or hasn't reached the secondary servers yet.
Frequently asked questions
It's the zone's version number and increases with every edit. Many providers use a date format such as 2026092001, meaning the first change on 20 September 2026.
It sets how long negative answers are cached — how long the world remembers that a name doesn't exist. A large value means a newly created subdomain can be slow to appear.
Because the DNS format doesn't permit @ there. So admin.example.com means [email protected].