Certificate Decoder
This certificate decoder decodes a PEM X.509 certificate to reveal its subject, issuer, validity and key details. It runs entirely in your browser, so results are instant and nothing you enter is uploaded.
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Your input is processed locally in your browser and is not uploaded or stored.
What this tool does
The standard structure for public-key certificates. This certificate decoder is free, works on desktop and mobile, and requires no sign-up.
Also useful for: csr decoder, pem decoder, ssl certificate decoder, x.509 certificate decoder.
Features
- Handles certificate decoder with instant, in-browser results
- No account, no upload and no usage limits
- Copy or download results in one click
How to use it
- Enter your input for the certificate decoder
- Read the result as it updates
- Copy or download what you need
Common uses
- Everyday certificate decoder work
- Quick checks while coding or writing
- Learning how the format behaves
Good to know
- For very large inputs, processing speed depends on your device
Related standards and concepts: X.509, RFC 5280.
Frequently asked questions
Is the certificate decoder free to use?
Yes. Every tool on the site is free, needs no account and has no usage limits.
Is my data uploaded anywhere?
No. The tool runs entirely in your browser, so your input never leaves your device.