www.shodan.io/ (IoT device search engine)
censys.io/ (Internet asset discovery platform)
www.zoomeye.org/ (Cyberspace search engine for devices)
www.greynoise.io/ (Internet noise and threat intelligence)
www.onyphe.io/ (Cyber defense search engine)
www.binaryedge.io/ (Threat intelligence data platform)
www.fofa.info/ (Cyberspace asset mapping engine)
leakix.net/ (Information leaks search engine)
www.criminalip.io/ (Asset inventory and risk assessment)
www.netlas.io/ (Attack surface discovery platform)
www.dehashed.com/ (Leaked credentials search engine)
securitytrails.com/ (DNS and domain data platform)
www.dorksearch.com/ (Google dorking search tool)
www.exploit-db.com/ (Exploit and vulnerability archive)
pulsedive.com/ (Threat intelligence search engine)
grayhatwarfare.com/ (Public S3 buckets search engine)
polyswarm.io/ (Threat detection marketplace)
urlscan.io/ (Website and URL scanning service)
vulners.com/ (Vulnerability database and search engine)
archive.org/web/ (Historical web page archive)
crt.sh/ (Certificate transparency search engine)
wigle.net/ (Wireless network mapping platform)
publicwww.com/ (Source code search engine)
hunter.io/ (Email address finder tool)
intelx.io/ (OSINT and data breach search)
grep.app/ (Code search engine for GitHub)
www.packetstomsecurity.com/ (Security tools and resources)
searchcode.com/ (Source code and API search engine)
www.dnsdb.info/ (Historical DNS data search)
fullhunt.io/ (Attack surface discovery platform)
www.virustotal.com/ (Malware analysis and file scanning)
dnsdumpster.com/ (DNS recon and research tool)