rdap

Look up who registered a domain and when it expires, using RDAP, the JSON successor to WHOIS. The client finds the right registry server from the IANA bootstrap registry, so there is no API key and no third-party service in between.

final rdap = RdapClient();
final domain = await rdap.domain('google.com');

print(domain.expires);           // 2028-09-14 04:00:00.000Z
print(domain.daysUntilExpiry()); // e.g. 729
print(domain.registrarName);     // MarkMonitor Inc.
print(domain.nameservers);       // [ns1.google.com, ns2.google.com, ...]

rdap.close();

Platform support

Pure Dart on top of package:http: Dart VM, Flutter on Android, iOS, Windows, macOS, Linux, and the web. The IANA registry and the major registries (Verisign for .com/.net, Public Interest Registry for .org, Google Registry for .dev) send Access-Control-Allow-Origin: *, so browser lookups work for them. A smaller registry without CORS headers can only be reached from a native app or a server.

Features

• Expiration, registration, and last-changed dates as DateTime.
• Registrar name and IANA Registrar ID, nameservers, EPP status values, and DNSSEC delegation.
• Server discovery through the IANA bootstrap registry (RFC 9224), downloaded once per client and retried if it fails.
• Stable error codes: unsupported_tld, not_found, timeout, http_error, and invalid_response.
• Internationalized names such as 한국.com are converted to Punycode (xn--3e0b707e.com), and unicodeName returns the Unicode form when the registry publishes it.
• raw keeps the full response for fields the model does not cover.

Installation

dependencies:
  rdap: ^0.0.2

Usage

final rdap = RdapClient(timeout: const Duration(seconds: 5));
try {
  final domain = await rdap.domain('example.com');
  if (domain.isExpired()) {
    print('${domain.ldhName} has expired');
  } else if ((domain.daysUntilExpiry() ?? 999) < 30) {
    print('${domain.ldhName} expires soon');
  }
} on RdapException catch (error) {
  switch (error.code) {
    case 'not_found':
      print('Not registered');
    case 'unsupported_tld':
      print('This TLD has no RDAP server');
    default:
      print(error);
  }
} finally {
  rdap.close();
}

Pass your own http.Client to share connections or to mock requests in tests. An injected client is not closed by close().

Limitations

• Only TLDs listed in the IANA bootstrap registry are supported (about 1,200). Many country-code TLDs, including .kr, .io, and .jp, are not listed and fail with unsupported_tld.
• Internationalized names are converted with Punycode only; UTS 46 mapping is not applied, so separate labels with . rather than a full-width 。.
• Registries rate-limit RDAP. Cache results instead of polling.
• Registries redact personal contact data, so registrant details are usually absent.

Flutter example

FutureBuilder<RdapDomain>(
  future: rdap.domain('seungpyo.online'),
  builder: (context, snapshot) {
    final domain = snapshot.data;
    if (domain == null) return const LinearProgressIndicator();
    return ListTile(
      title: Text(domain.ldhName),
      subtitle: Text('Expires in ${domain.daysUntilExpiry()} days'),
    );
  },
)