PEM to DER converter
To convert PEM to DER, drop your PEM file in the box below. It converts straight away; press Download to save the DER. It all happens in your browser, so your file stays on your device.
Convert to
What changes
| PEM to DER | What happens |
|---|---|
| One block | One .der file, byte for byte what the PEM holds |
| Several blocks | A ZIP with one .der file each, named after the certificate |
| Read | Certificates, requests, CRLs, PKCS#7, public and private keys |
| Not converted | OpenSSH keys and old OpenSSL-encrypted keys, which are not DER inside |
How to convert PEM to DER
- Add your PEM. Drop the file in the box, or click to choose it. It becomes DER straight away.
- Check the result. Look at the preview and the size. The defaults are right for most files.
- Download. Press Download to save the DER.
Windows, Java and some devices want certificates and keys in binary DER form instead of PEM text.
Questions
DER is the certificate’s binary form. PEM is the same bytes in base64 between BEGIN and END lines, so it can be pasted into text files and config.
No. PEM and DER are two wrappings of the same bytes: the fingerprints, signature and dates stay exactly the same.
A ZIP with three .der files, in the order they are in the PEM, each named after its certificate.
No. The file is read and converted in your browser, so it stays on your device.
No. The conversion happens right in your browser, so your file stays on your device. There is no account to make, either.