Every signal about a domain, in one REST call.
WHOIS, DNS, SSL, subdomains and email security for any domain, returned as clean JSON.
// Run a lookup to see the JSON response
Long arrays are shortened here. The API returns them in full.
curl "https://domain-intelligence-api.p.rapidapi.com/lookup/example.com" \
-H "X-RapidAPI-Host: domain-intelligence-api.p.rapidapi.com" \
-H "X-RapidAPI-Key: YOUR_RAPIDAPI_KEY"
import requests
r = requests.get(
"https://domain-intelligence-api.p.rapidapi.com/lookup/example.com",
headers={
"X-RapidAPI-Host": "domain-intelligence-api.p.rapidapi.com",
"X-RapidAPI-Key": "YOUR_RAPIDAPI_KEY",
},
timeout=30,
)
print(r.json())
// Node 18+ (built-in fetch)
const res = await fetch(
"https://domain-intelligence-api.p.rapidapi.com/lookup/example.com",
{ headers: {
"X-RapidAPI-Host": "domain-intelligence-api.p.rapidapi.com",
"X-RapidAPI-Key": "YOUR_RAPIDAPI_KEY",
} }
);
console.log(await res.json());
<?php
$ch = curl_init("https://domain-intelligence-api.p.rapidapi.com/lookup/example.com");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
"X-RapidAPI-Host: domain-intelligence-api.p.rapidapi.com",
"X-RapidAPI-Key: YOUR_RAPIDAPI_KEY",
]);
$data = json_decode(curl_exec($ch), true);
print_r($data);
What one call returns
Call /lookup for everything, or one endpoint at a time. Same key and price for all of them.
All five signals
Everything below, fetched in parallel. Add ?wait=1 to wait for every subdomain source to finish.
WHOIS / RDAP
Registrar, registration and expiry dates, nameservers, status. RDAP first, then port-43 WHOIS for 50+ TLDs.
GET/domain/{d}/whoisSSL certificate
Live TLS handshake: issuer, subject, validity dates, days until expiry, SANs.
GET/domain/{d}/sslSubdomains
Live hosts with their IPs, kept apart from historical names. From CT logs, passive DNS (25+ sources) and brute-force.
GET/domain/{d}/subdomainsEmail security
SPF and DMARC records, plus DKIM keys found on 29 common selectors.
GET/domain/{d}/email-securityResults are cached: DNS 5 min, WHOIS 1 h, SSL 6 h, subdomains 24 h, email security 1 h.
Pricing
Every plan includes all endpoints. Billed monthly through RapidAPI. Cancel anytime.
- 1,000 requests / month
- All endpoints
- No credit card
- 50,000 requests / month
- $0.0002 per request
- Overage $0.0005 / request
- Email support
- 500,000 requests / month
- $0.00008 per request
- 60% cheaper per request than PRO
- Overage $0.0002 / request
- Email support
- 5,000,000 requests / month
- $0.00003 per request
- 85% cheaper per request than PRO
- Overage $0.0001 / request
- Dedicated support channel
Requests over the monthly quota are billed at the overage rate. Cached responses count like fresh ones.
Compare with DomainTools, WhoisXMLAPI and Sublist3r
| OTI Labs | DomainTools | WhoisXMLAPI | Sublist3r (open source) | |
|---|---|---|---|---|
| Free tier | 1,000 requests/mo, no card | None | Limited trial | Free, self-hosted |
| Starting paid plan | $9.99/mo | $99/mo | ~$49/mo | n/a |
| WHOIS / RDAP | RDAP with port-43 WHOIS fallback | WHOIS | WHOIS + RDAP | — |
| DNS, SSL, subdomains and email in one call | Yes | Separate products | Separate endpoints | Subdomains only |
| Subdomains | CT logs, passive DNS (25+ sources), brute-force; live hosts with IPs | Passive DNS | Separate API | Passive sources + brute-force |
| Setup | Minutes (RapidAPI key) | Sales call | Account + verification | Install and run yourself |
| Hosted and cached | Yes | Yes | Yes | No |
| Source code | MIT on GitHub | No | No | Yes |
From public pricing pages, May 2026. Check each vendor for current plans.
What people build with it
Security and threat intel
Enrich indicators, check new look-alike domains, review certificates and DNS during an incident.
Attack surface monitoring
Track live subdomains, their IPs and new certificates for domains you own.
Lead enrichment
Mail provider from MX, domain age, DMARC posture and subdomain footprint before a lead enters your CRM.
Email deliverability
Check SPF, DMARC and DKIM before you send.
Registrar and hosting dashboards
Show live SSL, DNS and WHOIS status without running your own scrapers.
SaaS custom domains
Validate DNS and SSL when a customer connects a domain.
Free tools, no signup
Report for any domain
Everything the API returns, as a web page.
Change alerts BETA
Daily checks and an email when a domain's certificate, subdomains, DNS, WHOIS or email records change. Free for one domain. Start from any report page.
Open a reportOpen source
Built and run in production by Osiris Technical Institute. The API source is MIT-licensed.
View on GitHub