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RSA Key Generator

Generate secure 1024, 2048, or 4096-bit asymmetric RSA key pairs in PEM format.

Whenever possible, your data never leaves your device. Your security is our priority.

Key Pair Configuration

Public Key

Private Key

About this Tool

RSA (Rivest-Shamir-Adleman) is a public-key cryptosystem that is widely used for secure data transmission. Unlike symmetric algorithms (like AES) where the same key locks and unlocks the data, RSA uses an asymmetric key pair.

The Public Key can be shared openly with anyone. They use it to encrypt a message. However, once encrypted, that message can only be decrypted by the mathematically linked Private Key, which must be kept completely secret.

How to Use

1

Select Key Size

Choose your bit length. 2048-bit is the current industry standard. 4096-bit is highly secure but will take several seconds to generate in your browser.

2

Generate Key Pair

Click generate. Your browser will perform complex prime-number mathematics locally to construct a cryptographically secure PEM-formatted pair.

3

Securely Store Keys

Copy your Private Key and store it in a secure vault. You can safely share the Public Key with external services (like GitHub or remote servers).

Frequently Asked Questions

Generating an RSA key requires finding two massive, cryptographically secure prime numbers. Doing this prime-number generation in browser-based JavaScript on a 4096-bit scale is extremely CPU-intensive and can take up to 20 seconds on older devices.
Yes, provided the code runs entirely locally. Because this tool uses JavaScript to compute the keys on your own device's CPU, the unencrypted private key is never transmitted across the network.
No. That is the fundamental math behind RSA. While they are linked, current computing power would take millions of years to factor the massive prime numbers required to guess the private key from the public key.