Free WHOIS and RDAP domain lookup
Type a domain to see whether it is registered, who runs it, when it expires and which nameservers it uses. No account needed.
What the lookup shows
Registered or available
The answer comes from the registry itself. When a registry offers neither RDAP nor WHOIS, we check the DNS delegation and say so: the result reads "maybe available" rather than a guess.
Dates
Creation, last update and expiry dates as the registry records them. Expiry is the one to watch: it tells you when a taken name may come back on the market.
Registrar and status codes
Which registrar manages the domain and its EPP status codes, such as clientTransferProhibited or pendingDelete. Contact details appear when the registrar publishes them.
Nameservers and DNSSEC
The nameservers the domain points to and whether DNSSEC is enabled. Useful to spot a hosting change or a parked domain.
How a lookup works
- 1
Find the right registry
Every extension has its own registry. We resolve it from the IANA RDAP bootstrap, refreshed every night, so .com goes to Verisign and .fr to AFNIC.
- 2
Ask it over RDAP, or WHOIS port 43
RDAP is the structured successor of WHOIS: JSON instead of free text. For the registries without RDAP we query their WHOIS server directly.
- 3
Keep the answer
Each lookup is stored. Look up the same domain later and you get its registry history: transfers, renewals, nameserver changes. Add it to a watchlist and we check it again every night.
WHOIS or RDAP?
Same data, different format. WHOIS returns a block of text that every registry lays out differently; RDAP returns JSON with the same fields everywhere. ICANN made RDAP mandatory for gTLDs in 2019 and many country-code registries have followed. We use RDAP whenever it exists.
Read the full WHOIS vs RDAP comparisonLook up a domain by extension
Each extension page explains how we query its registry and lets you check a name in one click.
Questions about the lookup
Is the WHOIS lookup free?
Yes. Without an account you can run 5 lookups per minute and 50 per day. A free account removes those limits and adds bulk lookups, history and alerts.
Why are the owner's name and email hidden?
Since the GDPR came into force in 2018, most registrars redact the personal data of individuals. We show what the registry publishes and never fill the gaps. Registrant, admin and tech contacts appear when they are public.
How fresh is the result?
It depends on the answer. An available domain is checked again after 15 minutes, a domain on its way out of the registry after an hour, a domain registered for two more years after up to a week. Domains on a watchlist are refreshed every night whatever the case.
What does "maybe available" mean?
The registry of that extension offers neither RDAP nor a WHOIS server we can parse, so we only checked whether the domain is delegated in the DNS. No delegation usually means the name is free, but only the registrar can confirm it.
Can I check several domains at once?
With a free account, paste a list of domains (a spreadsheet column works) and Domain Sentinel runs the lookups for you, flags the names already on your watchlist and lets you add the rest. Developers can use the REST API instead.
From the blog
- What is WHOIS? Domain registration data explainedWHOIS is a public database of domain registration records. Learn what a WHOIS record contains, what you can find, and how it works.
- How to do a WHOIS lookup: 3 methods explainedThree ways to look up WHOIS data for any domain: a web tool, the command line, and a direct RDAP query. Step-by-step with examples.
- WHOIS vs RDAP: what changed and why it mattersRDAP is the modern replacement for WHOIS. Same data, but structured JSON over HTTPS instead of raw text on port 43. Here is what changed and why.
- How to read domain registration data: fields and codes explainedWhat every WHOIS and RDAP field means: registrant vs registrar vs registry, EPP status codes, expiry dates, nameservers. A practical reference.
Waiting for a domain to free up?
Add it to your watchlist. We check it every night and email you the day it becomes available, expires or changes hands.
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