RDAP (Domain Lookup) API
Free RDAP API with no key: structured JSON domain registration data — registrar, creation and expiry dates, nameservers and status. The modern WHOIS. Tested.
Endpoint tested and returned HTTP 200 on 2026-08-20
What is the RDAP (Domain Lookup) API?
RDAP (Registration Data Access Protocol) is the standardised, free replacement for WHOIS, returning domain registration data as structured JSON — registrar, creation and expiry dates, nameservers and status codes — with no API key.
WHOIS returns unstructured text that differs by registry and has to be scraped. RDAP is the IETF standard that replaced it, returning consistent JSON that you can actually parse reliably.
The rdap.org bootstrap service is the practical entry point: it looks up which registry is authoritative for a domain and redirects you there, so you do not need to maintain a mapping of TLDs to RDAP servers yourself. That redirect is expected behaviour, not an error.
Quick facts
- Base URL
https://rdap.org- Authentication
- No API key required. Some registries rate-limit by IP.
- Rate limit
- Varies by registry; the bootstrap service itself does not limit, but destination registries may.
- Pricing
- Free — it is an open internet standard.
- CORS
- Enabled — callable directly from browser JavaScript
- Official docs
- Read the docs
How to use the RDAP (Domain Lookup) API
Every request below was executed against the live API on 2026-08-20, and the response shown is the real body it returned — not an illustration.
1. Look up domain registration data
GET https://rdap.org/domain/example.com
curl 'https://rdap.org/domain/example.com'const res = await fetch("https://rdap.org/domain/example.com");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);import requests
res = requests.get("https://rdap.org/domain/example.com", timeout=20)
res.raise_for_status()
print(res.json()){
"objectClassName": "domain",
"handle": "2336799_DOMAIN_COM-VRSN",
"ldhName": "EXAMPLE.COM",
"links": [
{
"value": "https://rdap.verisign.com/com/v1/domain/example.com",
"rel": "self",
"href": "https://rdap.verisign.com/com/v1/domain/example.com",
"type": "application/rdap+json"
}
],
"status": [
"client delete prohibited",
"client transfer prohibited",
"client update prohibited"
],
"entities": [
{
"objectClassName": "entity",
"handle": "376",
"roles": [
"registrar"
],
"publicIds": [
{
"type": "IANA Registrar ID",
"identifier": "376"
}
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"fn",
{},
"text",
"RESERVED-Internet Assigned Numbers Authority"
]
]
],
"entities": [
{
"objectClassName": "entity",
"roles": [
"abuse"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"fn",
{},
"text",
""
],
[
"tel",
{
"type": "voice"
},
"uri",
""
],Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
domain/<name> | path | Required | Domain to look up. domain/example.com |
ip/<address> | path | Optional | IP address allocation data. ip/8.8.8.8 |
autnum/<asn> | path | Optional | Autonomous system registration. autnum/15169 |
Response fields
objectClassNamestring- Type of object returned — `domain`, `ip network` or `autnum`.
ldhNamestring- The domain name in LDH (letter-digit-hyphen) form.
handlestring- Registry's internal identifier for the registration.
statusarray- EPP status codes such as clientTransferProhibited.
eventsarray- Registration, expiry and last-changed dates with event actions.
nameserversarray- Authoritative nameservers for the domain.
entitiesarray- Registrar and contacts, usually redacted for privacy.
What you can build with the RDAP (Domain Lookup) API
- Check domain expiry dates and set renewal reminders
- Verify domain ownership signals during onboarding
- Build a domain research or due-diligence tool
- Replace fragile WHOIS text scraping with structured data
Common errors and how to fix them
Redirect to a registry host
That is how the bootstrap works.
Fix: rdap.org resolves the authoritative registry and redirects — follow it rather than treating it as an error.
Contact details redacted
GDPR and registry privacy policies redact most personal data.
Fix: Expect registrant details to be withheld; registrar and dates remain available.
404 for some TLDs
Not every ccTLD operates an RDAP service.
Fix: Coverage is complete for gTLDs but patchy for country-code TLDs.
RDAP (Domain Lookup) API — frequently asked questions
What is RDAP and why not just use WHOIS?
RDAP is the IETF standard that replaced WHOIS. WHOIS returns unstructured text that varies by registry and must be scraped; RDAP returns consistent, parseable JSON.
Is RDAP free?
Yes, it is an open internet standard with no API key. Individual registries may rate-limit by IP.
Why can't I see the domain owner's name?
GDPR and registry privacy policies redact registrant contact details for most domains. Registrar, dates, nameservers and status codes remain public.
Why does my request redirect?
rdap.org is a bootstrap service that finds the authoritative registry for the domain and redirects there. Following the redirect is the intended behaviour.
Tools that pair with this API
JSON Formatter
Format, beautify and minify JSON online with 2-space, 4-space or tab indentation. Sort keys alphabetically and catch syntax errors instantly — free and private.
Timestamp Converter
Convert timestamps to human-readable dates and dates back to timestamps. Auto-detects seconds vs milliseconds, shows local, UTC and ISO 8601 formats.
RDAP (Domain Lookup) is an independent third-party service and is not affiliated with ByteTools or ByteVancer. Details on this page were verified on 2026-08-20; always check the official documentation before relying on this API in production, as terms and limits can change.