Bulk email domain nameserver lookup: who runs the DNS behind each address?
In short: Paste email addresses and see each domain's nameservers, named by the company that runs them, with parking nameservers and domains that don't exist flagged. Limit: Reads the domain, never the mailbox: a nameserver says nothing about a particular address.
A bulk email domain nameserver lookup reads the domain after the @ in each address and returns its NS records, each named by the company that runs it. Paste up to 100 unique domains a run, or 500 signed in. Parking nameservers and domains that don't exist in DNS are flagged. It checks the domain, not the mailbox. Download the CSV.
Working nameservers don't prove a working mailbox. Check every address.
Price: this tool is free. Checking a whole email list is from $9/mo, and the first 100 checks are free with Google, no card. Check your list free nowSee pricing
Sample result
tom@globex.example is at a domain whose nameservers belong to a parking service.
- Address
- tom@globex.example
- Domain
- globex.example
- Provider
- Example Parking
What this means for you
Parking nameservers are a signal, not proof: a company can park a domain it isn't using yet.
- Nameservers named by company
- Parking nameservers flagged
- Missing domains flagged
- CSV out, nothing emailed
- NS
- Parking
- CSV
By SimpleVerifier Team · Last updated
Got a list with addresses at domains that may be parked or gone?
- Paste it above to see the nameservers and DNS provider behind each address's domain, with a CSV of every row.
- Upload or paste it at /verify. Every address gets a live mailbox check, and the first 100 email checks are free with a Google sign-in, no card.
How do I look up the nameservers for every email address on a list?
- Paste email addresses, one per line, or upload a CSV. Addresses are found anywhere in the text, so a whole export works.
- Press Look up nameservers. Only the unique domains are sent, never the mailbox names, 25 a request, and only public DNS is read. No website and no mail server is contacted.
- Read each row: the DNS provider's name, Parking nameservers, Unrecognised nameservers, No nameservers or Domain doesn't exist.
- Filter to the flagged addresses, download the CSV with the full nameserver list, and hand the rest to the mailbox check.
Example
- You enter
- Four addresses:
jane@acme.example(a DNS provider's nameservers),tom@globex.example(a parking service's nameservers),ana@initech.example(nameservers no company we recognise runs) andbo@umbrella.example(not in DNS). - You get
- jane: the DNS provider's name. tom: Parking nameservers. ana: Unrecognised nameservers. bo: Domain doesn't exist. The full nameserver list is in the CSV.
- Limits
- Up to 100 unique domains a run without an account and 500 when signed in with Google. 25 domains a request; DNS only.
What does a nameserver tell you?
The nameservers are the servers that answer for a domain, so the company behind them is where its DNS records are edited. They are often not the registrar. A domain's own nameservers, a DNS provider, a web host or a registrar can all appear, and the row names the one it recognises.
A domain with no NS records, or one that doesn't exist in DNS at all, has nowhere to deliver mail.
Why look at nameservers on an email list?
Nameservers that belong to a parking service are a signal the domain is parked or for sale, and addresses at a parked domain tend to go nowhere. It is a signal, not proof: a company can park a domain it isn't using yet. A list of thousands of addresses has far fewer unique domains, so the check is cheap.
For the website side of the same question, use the bulk email parked domain checker.
What do you do with the flagged rows?
Take Domain doesn't exist and No nameservers rows off the send list, and look at Parking nameservers rows by company name: the business may have moved to a new domain. To see who registered each domain, use the bulk email domain registrar lookup.
Before you email anyone on the rest, verify the addresses.
Who uses this tool, and for what?
- Marketers
- Drop addresses at domains that no longer exist in DNS before an import.
- Sales teams
- Skip leads whose company domain sits on parking nameservers.
- Agencies
- See who runs the DNS for every client-list domain.
- Developers
- Triage a signup export by DNS provider.
What can’t this tool tell you?
- Reads the domain, never the mailbox: a nameserver says nothing about a particular address.
- Parking nameservers are a signal, not proof; a provider we don't list shows as unrecognised.
- DNS only: no website or mail server is contacted, so a missing website is not seen here.
- Up to 100 unique domains a run without an account, 500 signed in. Free providers such as gmail.com are looked up like any domain.
Common questions
- How do I look up the nameservers for every email address on a list?
- Paste the list into a bulk email domain nameserver lookup like this one. It reads each address's domain and returns its NS records, each named by the company that runs it.
- Is this bulk email domain nameserver lookup free?
- Yes. It is a free tool: up to 100 unique domains a run with no account, and up to 500 a run when you sign in with Google, with no card.
- Does it tell me whether the mailbox exists?
- No. It checks the domain, not the mailbox. A domain with healthy nameservers can still hold a closed mailbox.
- Are parking nameservers proof a domain is parked?
- No. They are a signal. A company can park a domain on purpose, so look at the company by name before you drop it.
- Why does a row say Unrecognised nameservers?
- The nameservers match no company we recognise. They are listed in full in the CSV.
- Does it send an email to the domain?
- No. It reads public DNS only. It never contacts a website or a mail server.
Sources
A tidy list can still be full of dead addresses.
Extracting, deduplicating and syntax checks all work on the text of an address. None of them can tell whether the mailbox exists. Only the server that hosts it can answer that, through an SMTP check, and that is what the paid product does.
- Upload the cleaned file as it is: CSVs up to 100,000 rows
- A real SMTP mailbox check on every row, with catch-all detection
- Small list? Starter at $9/mo covers 2,500 emails a month, cancel anytime
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.