Peek509 is a lightweight VS Code extension that lets you decode and inspect X.509 certificates directly from .pem or .crt files. Right-click a certificate file or run the command from the palette to instantly view its contents in a clean, human-readable format. No terminal commands required.
Features
Decode .pem and .crt files via:
Right-click in Explorer
Command Palette (with file picker fallback)
Human-readable certificate viewer:
Subject and Issuer details
Validity period
Serial number
SHA-256 fingerprint
Signature preview
Public key details (RSA/ECDSA)
Opens decoded output in a virtual tab (no save prompt)
Clean indentation and aligned formatting for readability
Usage
Option 1: Right-click
Open your project in VS Code.
Right-click any .pem or .crt file in the Explorer.
Select "Peek509: Decode x509 Certificate".
A new tab will open with the decoded certificate.
Option 2: Command Palette
Open the Command Palette (Ctrl+Shift+P or Cmd+Shift+P).
Run "Peek509: Decode x509 Certificate".
Select a certificate file from anywhere on your system.
