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SSL/TLS Certificate Decoder

DeveloperNetworkingSecurity

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INPUT

Auto Process

OUTPUT

Client Side

Subject

Field	Value
Result will appear here

Issuer

Field	Value
Result will appear here

Validity

Field	Value
Result will appear here

Certificate Details

Property	Value
Result will appear here

Extensions

Extension	Value
Result will appear here

Fingerprints

Algorithm	Fingerprint
Result will appear here

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Guide

SSL/TLS Certificate Decoder

Decode and analyze SSL/TLS certificates instantly. Paste any PEM-encoded certificate to see its full details — subject, issuer, validity, extensions, and security warnings.

How to Use

Paste your PEM-encoded certificate (starting with —–BEGIN CERTIFICATE—–) into the input field. The tool instantly decodes and displays all certificate details including subject information, issuer chain, validity dates, public key details, and security analysis.

Features

Certificate Details – Subject, Issuer, Serial Number, Version, Signature Algorithm
Validity Analysis – Not Before/After dates with color-coded expiry countdown
Public Key Info – Algorithm type and key size
Extensions – SANs, Key Usage, Extended Key Usage
Fingerprints – SHA-256 and SHA-1 certificate fingerprints
Security Warnings – Detects expired, self-signed, weak key, and SHA-1 signatures