2s.io

● healthy general

Certificate Transparency recon for a domain — discover its subdomains and issued certificates from public CT logs (passive attack-surface mapping). Pass domain. Returns the deduplicated set of subdomains seen across all certs (subdomains + subdomainCount), and the certificates (issuer, validity window, SAN dns names), most recent first. Sourced from SSLMate certSpotter (primary) with a crt.sh fallback — keyless. Live CT-log data over a huge append-only dataset an LLM cannot enumerate. For extern

How to call

cURL · x402-fetch / x402-axios will auto-handle 402

curl -X POST https://2s.io

/.well-known/x402.json

https://2s.io/.well-known/x402