Domain Research API

Free access to domain intelligence data for qualified researchers and brand protection professionals. Apply via the contact button; approved applicants receive an API key bound to their IP range.

Overview

Two API services are available:

NRDS Search API

Search and analyze newly registered gTLD domains within the past 30 days. Supports brand impersonation monitoring, registration pattern analysis, and research on newly registered names.

Base URL			https://api.brandargus.com/v1/nrds-search
Domain Types			Major gTLDs (com, net, org, info, xyz, etc.)
Time Window			Rolling 30 days
Update Frequency			Daily

NS Reverse Lookup API

Identify all gTLD domains hosted under a specific nameserver infrastructure. Supports infrastructure correlation and portfolio mapping.

Base URL			https://api.brandargus.com/v1/ns-reverse
Data Scope			Active domains (daily snapshot)
Update Frequency			Daily

Both APIs are currently in Beta and provided free of charge for research purposes.

Quick Start

# NRDS: search domains containing "nike"
curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://api.brandargus.com/v1/nrds-search/domains?keyword=nike&tld=com"

# NS Reverse: find domains on a nameserver
curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://api.brandargus.com/v1/ns-reverse/domains?ns=ns1.example.com"

Authentication

All API requests require a Bearer token in the Authorization header. Your client IP must also be within the pre-authorized range.

IP Whitelist

IP Format			Single IP (e.g., 203.0.113.50) or CIDR range (e.g., 203.0.113.0/24)
IP Changes			Contact support. Changes may take up to 24 hours.
Dynamic IP			Not supported. Use a VPN or cloud server with static IP.

API requests from non-whitelisted IPs will be rejected with a 403 error.

Authentication Header

Authorization: Bearer <your-api-key>

Rate Limiting

Requests per minute			120
Recommended interval			1 request per second

Exceeding the limit returns a 429 Too Many Requests error.

Response Headers

X-RateLimit-Limit			Maximum requests per minute
X-RateLimit-Remaining			Remaining requests in current window
X-RateLimit-Reset			Unix timestamp when the rate limit resets

Rate Limit Response

HTTP/1.1 429 Too Many Requests
X-RateLimit-Limit: 120
X-RateLimit-Remaining: 0
X-RateLimit-Reset: 1706284800

{
  "error": "rate limit exceeded"
}

Error Codes

Code	Type	Description
400	HTTP	Invalid parameter, malformed cursor, or bad request
401	HTTP	Missing or invalid API key
403	HTTP	IP address not in allowed range
429	HTTP	Rate limit exceeded
500	HTTP	Internal server error

Error Response

{
  "error": "ip not in allowed range"
}

NRDS: Search Domains

GEThttps://api.brandargus.com/v1/nrds-search/domains

Search newly registered domains with flexible filtering and cursor-based pagination. Results are returned in database order.

Parameters

Parameter	Type	Default	Description
keyword	string	-	Search keyword in domain prefix (case-insensitive)
match	string	contains	Match type: contains, prefix, suffix
tld	string	all	Filter by TLD (e.g., com, net, org)
reg_date	string	-	Filter by exact registration date (YYYY-MM-DD). Shorthand for reg_after + reg_before on the same day.
reg_after	string	-	Registration date from, inclusive (YYYY-MM-DD)
reg_before	string	-	Registration date to, inclusive (YYYY-MM-DD)
pure_number	bool	-	If true, only pure numeric domains. If false, exclude them.
has_number	bool	-	If true, must contain numbers. If false, must not.
has_hyphen	bool	-	If true, must contain hyphens. If false, must not.
pure_alpha	bool	false	Only alphabetical domains [a-z]
min_len	int	-	Minimum domain prefix length
max_len	int	-	Maximum domain prefix length
limit	int	100	Results per page (max: 1000)
cursor	string	-	Pagination cursor from previous response

The ns field in the response contains multiple nameservers separated by semicolons (;). When next_cursor is null or absent, there are no more results.

Request

curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains?\
keyword=nike&tld=com&limit=100"

# Pagination
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains?\
keyword=nike&cursor=eyJvZmZzZXQiOjEwMH0"

# Hyphenated variants
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains?\
keyword=nike&has_hyphen=true"

# Filter by exact registration date
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains?\
reg_date=2026-04-07&tld=com"

# Short alphabetical domains
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains?\
pure_alpha=true&min_len=3&max_len=6"

Response

{
  "matched": 1542,
  "returned": 100,
  "next_cursor": "eyJvZmZzZXQiOjEwMH0",
  "domains": [
    {
      "domain": "nike-outlet-store.com",
      "reg_date": "2026-01-25",
      "exp_date": "2027-01-25",
      "ns": "ns1.example.com;ns2.example.com"
    }
  ]
}

NRDS: Count Domains

GEThttps://api.brandargus.com/v1/nrds-search/domains/count

Count matching domains without returning the full result set. Accepts the same filtering parameters as Search (except limit and cursor).

Request

curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains/count?\
keyword=nike"

Response

{
  "matched": 15432
}

NRDS: Export Domains

GEThttps://api.brandargus.com/v1/nrds-search/domains/export

Download matching domains as a CSV file. Accepts the same filtering parameters as Search (except limit and cursor).

Large exports with millions of domains may take several seconds. Set your HTTP client timeout to 30s+.

Response Headers

Content-Type			text/csv; charset=utf-8
Content-Disposition			attachment; filename=nrds-export.csv

Request

curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/nrds-search/domains/export?\
keyword=nike&tld=com" \
  -o domains.csv

Response (CSV)

domain,reg_date,exp_date,ns
nike-outlet.com,2026-01-25,2027-01-25,ns1.host.com;ns2.host.com
mynike-store.com,2026-01-24,2027-01-24,ns1.reg.com;ns2.reg.com

NRDS: Health Check

GEThttps://api.brandargus.com/v1/nrds-search/health

Check API service status and data freshness. No authentication required.

Response

{
  "status": "ok",
  "updated_at": "2026-01-26T02:30:00Z"
}

NS Reverse: Domain Count

GEThttps://api.brandargus.com/v1/ns-reverse/domains/count

Retrieve the total number of domains hosted under a specific nameserver.

Parameter	Type	Default	Description
nsREQUIRED	string	-	Nameserver FQDN (e.g., ns1.example.com)

Request

curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/ns-reverse/domains/count?\
ns=ns1.example.com"

Response

{
  "ns": "ns1.example.com",
  "total": 125432
}

NS Reverse: Query Domains

GEThttps://api.brandargus.com/v1/ns-reverse/domains

Query domains hosted under a specific nameserver with filtering and cursor-based pagination.

Parameters

Parameter	Type	Default	Description
nsREQUIRED	string	-	Nameserver FQDN (e.g., ns1.example.com)
limit	int	100	Results per page (max: 1000)
cursor	string	-	Pagination cursor from previous response
tld	string	all	Filter by TLD (e.g., com, net)
keyword	string	-	Filter by keyword in domain prefix (case-insensitive)
match	string	contains	Match type: contains, prefix, suffix
has_number	bool	-	If true, must contain numbers. If false, must not.
has_hyphen	bool	-	If true, must contain hyphens. If false, must not.
pure_alpha	bool	false	Only alphabetical domains [a-z]
min_len	int	-	Minimum domain prefix length
max_len	int	-	Maximum domain prefix length
reg_date	string	-	Filter by exact registration date (YYYY-MM-DD). Shorthand for reg_after + reg_before on the same day.
reg_after	string	-	Registration date from, inclusive (YYYY-MM-DD)
reg_before	string	-	Registration date to, inclusive (YYYY-MM-DD)

The domains array contains full domain names (e.g., "example.com"). When next_cursor is null or absent, there are no more results.

Request

curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/ns-reverse/domains?\
ns=ns1.example.com&tld=com&limit=100"

# Search by keyword
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/ns-reverse/domains?\
ns=ns1.example.com&keyword=bank&match=prefix"

# Filter by exact registration date
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/ns-reverse/domains?\
ns=ns1.example.com&reg_date=2025-06-15"

# Filter by registration date range
curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/ns-reverse/domains?\
ns=ns1.example.com&reg_after=2025-01-01&reg_before=2025-12-31"

Response

{
  "ns": "ns1.example.com",
  "total": 125432,
  "returned": 100,
  "next_cursor": "eyJvZmZzZXQiOjEwMH0",
  "domains": [
    "example.com",
    "domainkits.com",
    "brandargus.com"
  ]
}

NS Reverse: Export Domains

GEThttps://api.brandargus.com/v1/ns-reverse/domains/export

Download all domains as a CSV file. Supports the same filtering parameters as Query (except limit and cursor).

Large nameservers with millions of domains may take several seconds. Set timeout to 30s+.

Response Headers

Content-Type			text/csv; charset=utf-8
Content-Disposition			attachment; filename=ns1_example_com.csv

Request

curl -H "Authorization: Bearer sk-xxx" \
  "https://api.brandargus.com/v1/ns-reverse/domains/export?\
ns=ns1.example.com&tld=com&pure_alpha=true" \
  -o filtered.csv

Response (CSV)

domain,reg_date
example.com,2024-05-15
domainkits.com,2023-11-20
brandargus.com,

The reg_date field may be empty if registration date is unavailable.

NS Reverse: Health Check

GEThttps://api.brandargus.com/v1/ns-reverse/health

Check API service status and data freshness. No authentication required.

Response

{
  "status": "ok",
  "updated_at": "2026-01-23T20:30:00Z"
}

Changelog

v1.0.22026-04-07

Added reg_date parameter for single-day queries (both APIs)
Fixed NS Reverse date filtering: reg_after/reg_before are now fully inclusive at day level
Documented inclusive behavior for all date parameters

v1.0.12026-02-04

Added reg_after/reg_before date filtering for NS Reverse Lookup API

v1.0.02026-01-27

Initial release: NRDS Search API and NS Reverse Lookup API

Terms of Use

BrandArgus.com is operated by Lyalpha GmbH. API access is granted exclusively for legitimate protection and research purposes.

Permitted Use

Brand protection monitoring
Domain and infrastructure research
Academic and non-commercial research

Restrictions

Do NOT use for spamming, harassment, or illegal activities
No redistribution, sublicensing, or resale of raw data
API keys are non-transferable and bound to your registered IP range

GDPR Compliance

Data Minimization			No PII of domain registrants is provided
Log Anonymization			Requesting IPs are anonymized (last two octets masked)
Retention Period			Access logs retained for max 90 days
Account Termination			All logs deleted within 30 days upon request

Free Beta Access

This API is provided free of charge for research purposes. We welcome bug reports, feature suggestions, and feedback on data quality.

Lyalpha GmbH

Heinrichstr. 73, 40239 Düsseldorf, Germany
Registration: HRB 106435 | VAT ID: DE314044210

General terms: see our Terms of Service. Privacy: Privacy Policy. Legal disclosure: Imprint.