PEM ⇄ DER
Convert keys/certificates between PEM (Base64 text) and DER (binary). Paste your data, then click to dissect it. Everything runs on your device, nothing is sent to a server.
Everything runs in your browser. Your data is never sent to our servers.
Example
Example Input
-----BEGIN PUBLIC KEY-----…
Example Output
DER (hex) + DER (base64)
How to Use
- 1Paste your data (PEM/Base64/token) into the Input field.
- 2Click the button (or press Ctrl+Enter) to dissect it.
- 3Read the decoded result in the Output field.
About PEM ⇄ DER
PEM and DER are two packagings of the same cryptographic structure. DER is the binary ASN.1 encoding; PEM is simply DER Base64-encoded and wrapped in "-----BEGIN…-----" headers.
This tool auto-detects direction: paste PEM and it outputs DER (hex + Base64); paste DER (Base64/hex) and it wraps it into PEM.
Useful when a tool expects DER but you only have PEM, or vice versa. It is a pure format conversion — the key contents do not change.
FAQ
Are my data or keys sent to a server?
No. PEM ⇄ DER runs entirely in your browser using the Web Crypto API and client-side libraries. Your data, passwords, and keys never leave your device.