Security Tools

How to Use the RSA Key Pair Generator

2026-11-124 min readBy Apex Tool Station Team

Generate RSA 2048, 3072 or 4096-bit public and private key pairs in PEM format, locally in your browser.

100% free No signup Works in your browser

1. What is the RSA Key Pair Generator?

Create RSA key pairs for testing encryption, JWT signing (RS256), SSH-style experiments and API integrations. Keys are generated by your browser's Web Crypto API and exported in standard PEM format (SPKI public key, PKCS#8 private key). Nothing is uploaded, but for production servers we still recommend generating keys on the machine that will use them.

2. How to use the RSA Key Pair Generator

Here is the whole process, step by step. It takes less than a minute from opening the tool to seeing your result.

1Fill in the Key size, Algorithm, Public key, Private key — keep secret fields.
2Copy or download your result with the buttons under the output.

Press the "Generate key pair" button and your result appears on the page.

Everything runs in your browser — your files and text never leave your device.

3. What you can do with it

Run the tool with the "Generate key pair" button when your input is ready.
Save your result with the "Copy", "Download" buttons under the tool.

4. Tips for best results

Your text never leaves your device — The tool runs entirely in your browser using JavaScript. Nothing is uploaded, so you can paste private documents without worry. That also means there is no account to create and no file to upload.
It works on your phone too — Open the tool in any modern browser on Android or iPhone. The layout adjusts to the screen and everything works the same way on a small screen as on a desktop.
Save your result before you leave — Use the "Copy" button to keep a copy.