Registrar vs DNS Host vs Web Host: Which Company Does What for Your Domain
A domain can involve four different companies, and each does one job. The domain registrar lookup finds them side by side: the registrar and expiry from the registry's RDAP record, the DNS host from the nameservers, and the email provider from MX records. The website host checker adds the fourth, the web host.
The four roles
| Role | What it does | Where to find it |
|---|---|---|
| Registrar | Holds the registration; you renew and transfer here | Registry RDAP record |
| DNS host | Runs the nameservers; records are edited here | NS records |
| Web host | Serves the website | A or CNAME record, response headers |
| Email provider | Receives the mail | MX records |
One company can do all four, as many registrars offer. They are often split, and that is where problems start.
Step 1: look up the domain
Enter the domain, or paste a list. Emails, URLs and subdomains are reduced to the registered name, so mail.acme.co.uk is looked up as acme.co.uk. Press Find registrar and DNS host.
Step 2: read where it is registered
The registrar and expiry come from the registry. Generic TLDs run RDAP, the structured successor to WHOIS (ICANN). Registries for .io, .co and .de publish none, so the registrar shows as unknown for them; their own registry sites are the place to look.
Step 3: read where to edit DNS
It names the company behind the nameservers. Cloudflare, GoDaddy, Namecheap, Route 53 and others are recognised, with a link to that company's guide where one has been checked. If you registered at Namecheap but pointed the nameservers at Cloudflare, records added at Namecheap do nothing. Where do I edit my domain's DNS goes deeper.
Step 4: check the web host and the mail provider
The site and the mail follow different records. The web host comes from the A or CNAME and the headers, using the website host checker; the email provider is already in the lookup row. Moving one does not move the other. See how to find which company hosts a website.
Why this matters for email setup
SPF, DKIM, DMARC and MX are DNS records. Add them at the DNS host or they have no effect, which is a common reason a new record "isn't working". The domain email setup checker gives the values for Google Workspace, Microsoft 365 or Zoho once you know where to edit.
What this check cannot do
- It cannot show the registrar for TLDs without RDAP.
- It cannot move a domain or edit records.
- A CDN or proxy can hide the real web host.
- Registry data can change; it shows the record as of the lookup.
If you are about to send from the domain
Correct DNS and a good domain get mail to the door; the address still has to exist. Upload your list on the verify page: the first 100 email checks are free with a Google sign-in, no card. Each address comes back valid, risky or invalid with a reason, and nothing is sent to anyone on the list. For larger or recurring lists, see bulk email verification, list cleaning and pricing.
Look up your domains now
Paste them into the domain registrar lookup.
Common questions
What is the difference between a registrar and a DNS host?
The registrar holds the registration, where you renew and can transfer away. The DNS host runs the nameservers that answer for the domain, where records are edited. They can be the same company or different ones.
How do I find out who my registrar is?
Read the registry's RDAP record. The domain registrar lookup shows the registrar and expiry for most generic TLDs. Registries for .io, .co and .de publish no RDAP, so it shows as unknown there.
Why do my DNS changes at the registrar do nothing?
Usually the nameservers point elsewhere, such as Cloudflare or a web host. Records only take effect at whoever runs the nameservers.
Is the web host the same as the email provider?
Often not. The site follows the A or CNAME record and mail follows the MX records, so they can be different companies.
Can I check a list of domains?
Yes. Up to 100 a run without an account and 500 after a free Google sign-in, with a CSV download.
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.