Live TLS handshake against any public host: certificate fields, chain, protocol and cipher.
🔒 Real check: the server opens a TLS connection to the host you enter and reports the actual peer certificate. Internal/RFC1918/IP-literal targets are blocked.
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Status
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Common Name (CN)
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Subject Alt Names
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Issuer
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Valid From
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Valid Until
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Days Remaining
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Signature Algorithm
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Public Key
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Negotiated Protocol
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Negotiated Cipher
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Serial
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account_tree Certificate Chain
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info Deeper analysis
For a full vulnerability scan (Heartbleed, POODLE, cipher details), use SSL Labs: