SSL Certificate API
Check any website's SSL/TLS certificate as an API. Pass a domain and the service performs a live TLS handshake and returns the certificate's subject and issuer, the validity window, the exact number of days until it expires, whether it is currently valid and trusted by a standard CA chain, the negotiated TLS protocol, serial number, SHA-256 fingerprint, key size and the full list of Subject Alternative Names (SANs). A lean expiry endpoint returns a simple ok / expiring_soon / expired status, perfect for uptime and certificate-expiry monitoring, dashboards, CI checks and security tooling. Self-contained — no third-party service. IP addresses and internal hosts are not supported.
api.oanor.com/sslcheck-api
