Paste a PEM certificate or key to convert it to binary DER format (and back), entirely client-side.
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Paste a PEM certificate or key to convert it to binary DER format (and back), entirely client-side. Common questions — like is it safe to paste sensitive data into this tool — are answered in the FAQ below.
Add your input to the workspace above, review the result, then copy or download it when it's ready. No account or installation is required.
PEM to DER Converter runs in your browser, so the information you enter stays on your device instead of being uploaded to a server.
A few worked examples so you know what to expect before you paste in your own input.
Input
(paste your security input above)
Output
Paste a PEM certificate or key to convert it to binary DER format (and back), entirely client-side.
What PEM and DER actually are, when to convert between them, and how to decode an X.509 certificate's subject, issuer, and validity without OpenSSL memorization.
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