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The RDAP CLI supports multiple query types defined by the RDAP RFCs. The tool can automatically detect the query type from your input, or you can specify it explicitly.

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Auto-Detection

The tool uses intelligent pattern matching to determine query type:
1

AS Number Detection

Queries starting with “AS” followed by digits, or pure numeric queries, are detected as AS numbers:
  • AS15169 → Autnum query
  • 15169 → Autnum query
2

IP Address Detection

Queries containing colons (IPv6) or matching IPv4 patterns are detected as IP queries:
  • 8.8.8.8 → IP query
  • 2001:db8::1 → IP query
  • 1.1 → IP query (normalized to 1.0.0.1)
  • 8.8.8.0/24 → IP query (CIDR notation)
3

TLD Detection

Single-word queries matching the IANA TLD list are detected as TLD queries:
  • google → TLD query (queries .google TLD)
  • com → TLD query (queries .com TLD)
  • io → TLD query (queries .io TLD)
4

Domain Fallback

Everything else defaults to domain queries:
  • example.com → Domain query
  • google.com → Domain query
The TLD detection uses the official IANA TLD list (tlds.txt) which is updated via rdap --update.

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Lookup Query Types

These query types retrieve a single object from the RDAP server.

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Domain

Query domain name registration information. 
# Auto-detected
rdap example.com

# Explicit type
rdap -t domain example.com
Returns: Domain object with nameservers, status, registrar, dates, and entities Special behavior: Automatically follows registrar referrals for multi-layer RDAP data

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TLD (Top-Level Domain)

Query TLD information from IANA. 
# Auto-detected
rdap google
rdap com

# Explicit type
rdap -t tld io
Returns: Domain object from IANA RDAP with TLD delegation information Server: Always queries https://rdap.iana.org/

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IP Address

Query IP address or network information. 
# IPv4
rdap 8.8.8.8
rdap 8.8.8.0/24

# IPv6
rdap 2001:db8::1
rdap 2001:db8::/32

# Shorthand (auto-normalized)
rdap 1.1          # → 1.0.0.1
rdap 1.2.3        # → 1.2.0.3

# Explicit type
rdap -t ip 192.0.2.1
Returns: IP Network object with address range, type, country, and abuse contact Normalization: Shorthand IPs are automatically expanded (e.g., 1.1 → 1.0.0.1) 
rdap 8.8.8.8

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Autnum (AS Number)

Query Autonomous System number information. 
# With AS prefix
rdap AS15169

# Without AS prefix
rdap 15169

# Explicit type
rdap -t autnum 8888
Returns: Autnum object with AS number, name, type, country, and abuse contact Format: Accepts with or without “AS” prefix

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Entity

Query entity (organization, person, contact) information. 
# Requires explicit server
rdap -s https://rdap.db.ripe.net -t entity XTOM-RIPE
Returns: Entity object with contact information (vCard), roles, and handles
Entity queries typically require specifying the RDAP server with -s since there’s no global bootstrap for entities.

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Nameserver

Query nameserver information. 
# Requires explicit server
rdap -s https://rdap.verisign.com/com/v1 -t nameserver ns1.google.com
Returns: Nameserver object with hostname and IP addresses

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Search Query Types

Search queries return multiple matching objects. These require explicit type specification. Search for domains by name pattern. 
rdap -s https://rdap.example.com -t domain-search "example*"
Endpoint: GET /domains?name={pattern}

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Domain Search by Nameserver

Find domains using a specific nameserver. 
rdap -s https://rdap.example.com -t domain-search-by-nameserver ns1.example.com
Endpoint: GET /domains?nsLdhName={nameserver}

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Domain Search by Nameserver IP

Find domains whose nameservers use a specific IP. 
rdap -s https://rdap.example.com -t domain-search-by-nameserver-ip 192.0.2.1
Endpoint: GET /domains?nsIp={ip} Search for nameservers by name pattern. 
rdap -s https://rdap.example.com -t nameserver-search "ns*.example.com"
Endpoint: GET /nameservers?name={pattern}

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Nameserver Search by IP

Find nameservers using a specific IP address. 
rdap -s https://rdap.example.com -t nameserver-search-by-ip 192.0.2.1
Endpoint: GET /nameservers?ip={ip} Search for entities by name. 
rdap -s https://rdap.example.com -t entity-search "Example Corp"
Endpoint: GET /entities?fn={name}

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Entity Search by Handle

Search for entities by handle/identifier. 
rdap -s https://rdap.example.com -t entity-search-by-handle ABC-123
Endpoint: GET /entities?handle={handle}
Search queries are not widely supported by all RDAP servers. Many servers only support direct lookups.

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Explicit Type Specification

Override auto-detection by specifying the query type: 
rdap -t domain example.com
rdap -t ip 8.8.8.8
rdap -t autnum 15169
rdap -t tld google
  • domain - Domain name lookup
  • tld - Top-level domain lookup
  • ip - IP address/network lookup
  • autnum - AS number lookup
  • entity - Entity lookup
  • nameserver - Nameserver lookup
  • domain-search - Domain search
  • domain-search-by-nameserver - Domain search by NS
  • domain-search-by-nameserver-ip - Domain search by NS IP
  • nameserver-search - Nameserver search
  • nameserver-search-by-ip - Nameserver search by IP
  • entity-search - Entity search by name
  • entity-search-by-handle - Entity search by handle

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Auto-Detection Logic

The detection algorithm (implemented in src/request.rs:detect_type_with_tld_check): 
// Pseudocode
if query starts with "AS" and rest is digits:
    return Autnum
else if query is all digits:
    return Autnum
else if query looks like IP (contains : or matches IPv4 pattern):
    return Ip
else if query has no dots AND matches IANA TLD list:
    return Tld
else:
    return Domain (default)

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Help Query

Query the RDAP server’s help endpoint: 
rdap -s https://rdap.example.com -t help help
Returns server-specific help information.

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Next Steps

Basic Queries

Start with basic RDAP queries

Output Formats

Learn about JSON and text output

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