Why This Exists
After Mastercard acquired Recorded Future for $2.65 billion (closed Q1 2025), SecurityTrails — which Recorded Future had previously acquired for $65 million — became a subsidiary of a credit card company. The free tier was cut to 50 queries/month. Paid plans now range from $11,000 to $70,000/year with an average of $34,000.
Open Domain Intel gives you the same core intelligence — DNS, WHOIS, SSL, tech detection, subdomains, security headers — running on your own server, querying only public data sources. No SecurityTrails account, no API keys, no query limits, no annual contract.
6 Intelligence Modules
DNS Records
A, AAAA, CNAME, MX, NS, TXT, SOA, SRV, CAA. Auto-detects mail provider (Google, O365, Proton) and DNS provider (Cloudflare, Route53). Checks SPF, DMARC, DKIM.
WHOIS / RDAP
Queries RDAP first (ICANN standard since Jan 2025) for structured JSON. Falls back to raw WHOIS. Returns registrar, creation/expiry dates, status, registrant info.
SSL Certificates
Full certificate chain, issuer, SAN list, days until expiry, DV/OV/EV type detection, signature algorithm. Catches expiring certs before they break.
Technology Detection
Identifies 50+ technologies: CMS (your server, Shopify), frameworks (React, Next.js, Laravel), analytics (GA4, Plausible), CDN, server software, and more.
Subdomain Discovery
Certificate Transparency log search (crt.sh) + DNS brute force of 100+ common prefixes. Same technique used by Subfinder, Amass, and SecurityTrails.
Security Headers
Checks HSTS, CSP, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy. Returns A/B/C/D grade with pass/fail per header.
SecurityTrails vs Open Domain Intel
| Feature | SecurityTrails | Open Domain Intel |
|---|---|---|
| DNS records | Yes | Yes (all types) |
| WHOIS/RDAP | Yes | Yes (RDAP-first) |
| SSL certificates | Pro+ only | Yes (free) |
| Subdomains | Yes | Yes (CT + brute) |
| Tech detection | Yes | Yes (50+ techs) |
| DNS history | Yes (massive DB) | No (live only) |
| IP neighbors | Yes | No |
| Passive DNS feeds | Enterprise only | No |
| Self-hosted | No | Yes |
| Query limits | 50/mo free, then $$$ | Unlimited |
| Price | $11,000–$70,000/yr | $0 forever |
What Open Domain Intel doesn't do: historical DNS data (SecurityTrails has a massive proprietary database of past DNS records), reverse IP lookups, and passive DNS feeds. These require large-scale data collection infrastructure. Open Domain Intel focuses on live, real-time intelligence from public sources — which covers the vast majority of investigative use cases.
Quick Start
Step 1. Download and upload to your server. Point your domain to the /public directory.
Step 2. Make /cache writable. Visit /admin to configure (default password: changeme).
Step 3. Use it:
# Full report (all 6 modules)
curl "https://yoursite.com/api/lookup?domain=github.com" | jq .
# Individual modules
curl "https://yoursite.com/api/dns?domain=github.com"
curl "https://yoursite.com/api/whois?domain=github.com"
curl "https://yoursite.com/api/ssl?domain=github.com"
curl "https://yoursite.com/api/tech?domain=github.com"
curl "https://yoursite.com/api/subdomains?domain=github.com"
curl "https://yoursite.com/api/headers?domain=github.com"API Endpoints
GET /api/lookup?domain={domain} → Full report (all modules)
GET /api/dns?domain={domain} → DNS records + SPF/DMARC/DKIM
GET /api/whois?domain={domain} → RDAP or WHOIS
GET /api/ssl?domain={domain} → SSL certificate details
GET /api/tech?domain={domain} → Technology fingerprinting
GET /api/subdomains?domain={domain} → Subdomain discovery
GET /api/headers?domain={domain} → HTTP headers + security grade
GET /api/status → Health checkEmbedding in Your Site
[domain_intel domain="github.com" module="dns"]
[domain_intel domain="github.com" module="ssl"]
[domain_intel domain="github.com" module="tech" format="json"]Requirements
PHP 7.4+ with OpenSSL, Apache (mod_rewrite) or Nginx, allow_url_fopen = On. No database. No Composer. No npm. No your server. Works on shared hosting, VPS, or dedicated servers.
License
GPLv2 or later. Free to use, modify, and distribute. Built by Max Intel. See all self-hosted tools.