Reading WHOIS and RDAP: what's in there and why don't you see an expiration date for .nl?
Want to know which registrar a domain is with, which nameservers it uses or since when it has existed? You can look that up in WHOIS or in RDAP. In this article you'll read what the difference is, which fields you'll come across and why you don't see an expiry date for a .nl domain.
WHOIS and RDAP: what's the difference?
WHOIS is the old system. You send a query via port 43 or via a web page of the registry and get a block of text back. Each registry uses its own format: at one a field is called "Registrar", at another "Sponsoring Registrar".
RDAP (Registration Data Access Protocol) is its successor. You send the query via regular https and the answer comes in a fixed format: JSON. This means any program can read it. RDAP is an official internet standard (RFC 9082 and RFC 9083).
For .com and the other gTLDs, RDAP has been the official source since 28 January 2025. Country code extensions make their own choice. SIDN offers both for .nl: a Whois and an RDAP service. The registries of .de, .eu and .be do not have a public RDAP (as of November 2026); there you use the WHOIS or the search function on the registry's website.
WHOIS and RDAP show what is recorded at the registry. What the DNS of your domain actually answers may differ from that, for example right after a change of nameservers.
The fields you'll come across
| Field | What it tells you |
|---|---|
| Status | Whether the name is active, blocked, deleted or being transferred |
| Registrar | The company where the name is registered; for .nl, any reseller is listed separately |
| Registration date | When the name was registered |
| Last changed | When something was last changed in the registration |
| Expiry date | Until when the registration at the registry runs (not for every extension) |
| Nameservers | The nameservers the registry points to |
| DNSSEC | Whether there is a DS record at the registry |
| Contacts | The registrant and contact persons, insofar as they are public |
In RDAP, the dates are in a list of events: "registration", "last changed" and, if the registry publishes it, "expiration". The registrar is listed as an entity with the role "registrar". You can read DNSSEC in the secureDNS block: if delegationSigned is set to true, there is a DS record at the registry and the domain is secured with DNSSEC. A highly simplified response:
{
"ldhName": "example.com",
"status": ["client transfer prohibited"],
"events": [
{"eventAction": "registration", "eventDate": "..."},
{"eventAction": "expiration", "eventDate": "..."}
],
"nameservers": [{"ldhName": "ns1.example.net"}],
"secureDNS": {"delegationSigned": true}
}
You can read what the codes under Status mean in Domain status codes: what do they mean and what should you do?.
Why don't you see an expiry date for .nl?
SIDN's Whois and RDAP don't show an expiry date, only the registration date and the date of the last change. How long your registration runs and when you renew is something you arrange with your registrar. For .com, you do see an expiry date in RDAP. .nl differs in other ways too:
- The .nl Whois uses SIDN's own statuses, such as Active, Inactive and In quarantine. SIDN's RDAP shows "active", and sometimes "locked".
- For private registrants, the .nl Whois doesn't show a name; for organisations it does. You do see, among other things, the registrar, the reseller, an email address to reach the registrant, DNSSEC yes or no and the nameservers. SIDN's RDAP shows "REDACTED FOR PRIVACY" for private individuals.
You can read what is public per extension and how to shield your details in Anonymous domain registration and WHOIS privacy.
Where do you look it up?
- The WebOké WHOIS lookup: www.weboke.nl/en/toondomein, also in the Tools menu. You'll see the registry's response, including the status, the registrar and the nameservers. The tool uses WHOIS via port 43 and therefore also works for extensions without a public RDAP. See also WHOIS, IP Lookup and SSL checker.
- SIDN's RDAP for .nl: rdap.sidn.nl. You put the name after /domain/ in the address and your browser shows the JSON.
- ICANN Lookup: lookup.icann.org looks up any extension that has RDAP and finds the right server by itself.
Want to learn more? Take the free course Choosing and managing a domain name, lesson 4.1 WHOIS and RDAP: how to look up a domain.