Certificate Transparency Subdomain Search (crt.sh alternative)

SSL Certificate Transparency Search

ryanclinton/crt-sh-search

Search Certificate Transparency (CT) logs via crt.sh to discover every SSL/TLS certificate ever issued for any domain. Enumerate subdomains, audit certificate histories, and monitor for unauthorized certificate issuance -- all through a clean JSON API on Apify with no infrastructure to manage.

Subdomain Finder - Discover Every Subdomain Of A Domain

thirdwatch/subdomain-finder

Discover every subdomain for any apex domain. Merges 4 sources: certificate transparency (crt.sh), HackerTarget, RapidDNS, plus DNS bruteforcing of common names. Verifies each is live via DNS + HTTP probe.

Map a domain's external attack surface. Passive subdomain enumeration with subfinder, HTTP fingerprint with httpx: status, title, server, technology stack, TLS issuer and IP. One dataset row per responding host. For recon, asset discovery and security audits.

Subdomain Finder

happitap/subdomain-finder

Subdomain Finder is a high-speed intelligence tool that uncovers subdomains for any target domain using Certificate Transparency (CT) logs. Unlike traditional brute-force tools, it requires no heavy traffic and provides results in seconds.

Subdomain Finder & Reverse IP

canadesk/subdomain-finder-reverse-ip

Enumerate Subdomains and Reverse IPs with RapidDNS, Anubis, AlienVault and crt.sh! It's fast and costs little.

🔍 Subdomain Finder & CT Log Scraper

taroyamada/subdomain-finder

Map website architectures by extracting subdomains from public Certificate Transparency logs to find unlinked staging sites.

Discover subdomains for any target via passive OSINT sources. Ideal for security bug bounties and attack surface mapping.

Real Subdomain Finder

onescales/real-subdomain-finder

Discover every subdomain for any domain. Queries 40+ OSINT sources including cert transparency, DNS archives & web scanners. Results enriched with DNS validation, HTTP probing, and subdomain takeover detection. Simple Subdomain Lookup that works!

Subdomain Discovery API

crawland/subdomain-discovery-api

Paginated subdomain enumeration for any registered domain — DNS records, registrar, WHOIS, vendor reputation, and category labels per subdomain, served from the Crawland threat-intelligence backend.

SSL Certificate Checker

automation-lab/ssl-certificate-checker

SSL Certificate Checker connects to domains over TLS and inspects their SSL certificates. It returns structured data about certificate validity, expiry, issuer chain, TLS protocol version, cipher suite, and a security grade from A+ to F.