Self-Signed Certificate Generator

Generate an RSA key + self-signed X.509 cert (with SANs) and export PEM / DER / .p12 — keys stay local.

Generate an RSA key + self-signed X.509 cert (with SANs) and export PEM / DER / .p12 — keys stay local. Free and 100% private — runs entirely in your browser, nothing is ever uploaded.

About Self-Signed Certificate Generator

Self-Signed Certificate Generator is a free, browser-based privacy & security tool that lets you generate an RSA key + self-signed X.509 cert (with SANs) and export PEM / DER / .p12 — keys stay local. Because it runs entirely on your device, there’s nothing to install, no account to create, and your data is never uploaded to a server.

How to use Self-Signed Certificate Generator

  1. Open Self-Signed Certificate Generator — it loads in any modern browser, with no sign-up.
  2. Paste or type your input.
  3. Get the result instantly, processed locally on your device.
  4. Copy or download the output — what you entered is never sent anywhere.

Frequently asked questions

Is Self-Signed Certificate Generator free?
Yes — Self-Signed Certificate Generator is completely free, with no account, sign-up or usage limits.
Is my data private?
Yes. Self-Signed Certificate Generator runs 100% in your browser, so your files and text are processed on your own device and never uploaded.
Do I need to install anything?
No — Self-Signed Certificate Generator works in any modern desktop or mobile browser with nothing to download.