RSA Key Pair Generator
Generate an RSA key pair in PEM format, entirely in your browser.
Protect your private key. Anyone who has it can decrypt your messages and impersonate you. Never share it, never paste it into websites you don't trust, and store it somewhere safe. This page does not save it: if you close the tab without downloading it, it is gone.
🔒 Your data is processed locally in your browser and is never uploaded to our servers.
How it works
Your browser generates the key pair with the Web Crypto API (RSA, public exponent 65537, SHA-256) using its secure random number generator. The public key is exported in SPKI PEM format and the private key in PKCS#8 PEM format, the formats used by OpenSSL and most languages.
Security notes
The private key is not encrypted with a passphrase. Store it like a password. Keys here are created as RSA-OAEP keys; as good practice, use separate key pairs for encryption and for signing. RSA-2048 is generally considered adequate today; larger sizes are slower and rarely necessary.
FAQ
Why is RSA-4096 slow?
Finding two very large random primes takes time, especially on phones. It can take several seconds.
Is the key really generated on my device?
Yes. Generation and export happen in your browser; no network request is made with your keys.