Short answer
Look up the website's IP address and see which company owns it. That company is the host, or a CDN in front of the host. The registrar and the DNS provider are different companies and do not show where the site actually lives. A whois lookup that also resolves the IP shows all three.
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Three different companies
People mix up three things. The registrar is where the domain was bought. The DNS provider answers the question of where the domain points. The host is the company whose server holds the website files.
They can be the same company, and often are for small sites. They are just as often three separate ones, which is why the whois record alone does not tell you the host.
The reliable method: follow the IP address
Every website name resolves to an IP address. Look up who owns that address and you have the network it runs on. The owner is shown as an organisation and a network number.
Our free whois lookup does this in one step. It resolves the domain, looks up the first address and shows the hosting organisation, network and location next to the registrar and name servers.
Try it now: Whois Lookup →
When a CDN hides the real host
Many sites sit behind a CDN or a security layer such as Cloudflare. The address you see then belongs to the CDN, not the server behind it. The lookup will correctly name the CDN, and that is the honest answer to who answers requests for the site.
The origin server is deliberately hidden. If you own the site, your hosting account or invoices tell you the real host. If you do not, you cannot reliably find it, and trying to is not a good use of time.
Clues from the name servers
The name servers in the record often name the DNS provider, and for small sites that is frequently the host too. Names containing a hosting brand are a strong hint. Names containing Cloudflare tell you DNS goes through Cloudflare, nothing more.
Why the location may not match the server
The location shown for an address is where it appears to be from the machine doing the lookup. A CDN answers from the nearest of its many locations, so the city can be different every time. For a site with a single server, it is a useful guide to where the data centre is.
What to do with the answer
If you are choosing hosting, ask how fast an uncached page loads rather than reading the host's name. A slow server behind a fast cache hides the problem until the cache misses.
If you are checking a competitor, remember hosting rarely explains why they rank. Content, links and speed do.