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Security & Crypto

RSA Keypair Generator & Encryption

Generate cryptographically secure 2048-bit & 4096-bit RSA asymmetric keypairs with live encryption testing in browser memory.

Quick Answer & Summary

An RSA keypair generator creates a mathematically linked public key (for encryption and signature verification) and private key (for decryption and signing) based on the computational difficulty of factoring large prime numbers.

RSA Asymmetric Cryptography Formula
Public Key: (n, e) | Private Key: (n, d) | Ciphertext c = m^e mod n | Plaintext m = c^d mod n

Where n = p × q is the modulus, e = 65537 is the public exponent, and d is the modular multiplicative inverse of e modulo φ(n).

RSA Key Parameters
100% WebCrypto In-Memory

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Documentation & Guide

How to Use RSA Keypair Generator & Encryption

1

Choose Modulus & Hash Strength

Select 2048-bit (standard) or 4096-bit (high security) along with SHA-256 or SHA-512 hashing.

2

Generate Keypair

Click Generate to create cryptographically secure asymmetric keys entirely in browser RAM.

3

Export PEM or Test Live

Copy or download .pem files, or type a secret message to test public-key encryption and private-key decryption.

Practical Examples & Conversions

Input
Modulus: 2048, Hash: SHA-256, Algorithm: RSA-OAEP
Output
SPKI Public Key (~450 chars) + PKCS#8 Private Key (~1700 chars)

Frequently Asked Questions (PAA)

Related Tools & Converters

Authoritative Standards & Citations

Calculations and algorithms on this page are implemented and verified in strict accordance with the following official technical specifications: