RSA Key Generator

RSA Key Generator — Generate Key Pairs Online

RSA Key Generator creates RSA key pairs using the Web Crypto API, outputting keys in standard SPKI (public) and PKCS#8 (private) PEM format.

Select your desired key size from the dropdown (1024, 2048, or 4096 bits) and click Generate. The tool creates an RSA key pair using the Web Crypto API's RSA-OAEP algorithm with SHA-256 hashing. The public key exports in SPKI (SubjectPublicKeyInfo) PEM format, while the private key exports in PKCS#8 PEM format. Both keys display in the output fields with copy buttons. Use the public key for encryption or signature verification, and keep the private key secret for decryption or signing. All key generation happens locally in your browser.

Developers setting up SSL/TLS certificates generate RSA key pairs for test environments or self-signed certificates. Security engineers create key pairs for testing asymmetric encryption implementations in applications. Backend developers generate keys for JWT signature verification or API authentication systems using RSA signatures. System administrators create SSH key pairs for server access, though this tool outputs PEM format rather than OpenSSH format.

Use 2048-bit keys minimum for production use; 1024-bit keys are no longer considered secure. 4096-bit keys provide extra security margin but are slower to generate and use; 2048-bit is the practical standard for most applications. Store private keys encrypted and never commit them to version control or share them over insecure channels. PEM format is widely compatible but includes header/footer markers and Base64 encoding; some tools need raw DER format instead. For SSH access specifically, use 'ssh-keygen' rather than this tool since SSH uses a different key format.

All processing happens directly in your browser. Your files never leave your device — no server uploads, no cloud storage, no data retention. The tool works offline once loaded, requires no registration, and is completely free with no usage limits.