How to Look Up the Nameservers for Every Email Address on a List
To look up the nameservers for every email address on a list, read the NS records of the domain after each @. The bulk email domain nameserver lookup does this for every address in a pasted list or CSV and gives each one a row naming the company that runs the domain's DNS, with parking nameservers and missing domains flagged.
The check reads DNS only, and the domain, not the mailbox.
Why look at nameservers on an email list
The nameservers are the servers that answer for a domain. When they belong to a parking service, the domain is often parked or for sale, and the addresses at it tend to go nowhere. When the domain is not in DNS at all, mail to it will bounce. A list of thousands of addresses has far fewer unique domains, so checking by domain is cheap.
The by-hand way
- Take the domain after the @, for example
acme.examplefromsam@acme.example. - Query its NS records with any DNS tool, or use a bulk nameserver lookup.
- Match the nameserver names to the company that runs them.
- Repeat for every unique domain.
Step 1: paste the addresses
Paste addresses one per line, or upload a CSV. Only the unique domains are sent, never the mailbox names, 25 a request.
Step 2: run the lookup
Press Look up nameservers. Public DNS is read; no website and no mail server is contacted.
Step 3: read the result
| Result | What it means |
|---|---|
| A DNS provider's name | The company that runs the nameservers |
| Parking nameservers | The nameservers belong to a parking service; a signal, not proof |
| Unrecognised nameservers | They match no company we know; the CSV lists them |
| No nameservers | No NS records were found for the domain |
| Domain doesn't exist | The name is not in DNS; mail will bounce |
The CSV carries the provider names and the full nameserver list beside each address. Parking, no-nameserver and missing-domain rows are left out of the list handed on to the mailbox check.
What this check cannot do
- It checks the domain, not the mailbox.
- Parking nameservers are a signal, not proof.
- It reads DNS only, so a missing website is not seen here.
- Up to 100 unique domains a run without an account, 500 signed in.
To see the website side of parking, use the bulk email parked domain checker, described in how to find email addresses at parked domains.
Next: the rest of the list
For the addresses that remain, use the verify page: the first 100 checks are free with a Google sign-in, no card.
Try it now
Paste your list into the bulk email domain nameserver lookup at simpleverifier.com.
Common questions
How do I look up the nameservers for every email address on a list?
Take the domain after the @ in each address and read its NS records. A bulk email domain nameserver lookup does that for every address in a pasted list and names each nameserver by the company that runs it.
Are parking nameservers proof a domain is parked?
No. They are a signal. A company can park a domain it is not using yet, so look at the company by name before you drop it.
What does Domain doesn't exist mean?
The name is not in DNS, so mail to it will bounce.
Is the DNS provider the same as the registrar?
Often not. The nameservers are where records are edited, and that can be a different company from the one the domain was bought from.
Does the check tell me whether the mailbox exists?
No. It checks the domain, not the mailbox.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.