RSA Key Generator

Generate public and private RSA key pairs.

Runs in your browser — your data never leaves your device

RSA Key Generation Options

Key Size (bits)

Public Key

Private Key

Generate RSA public and private key pairs for encryption, decryption, and digital signing. Choose between 1024, 2048, and 4096-bit key sizes and download the keys in PEM format for use in your applications.

What is RSA?

RSA is one of the most widely used public-key cryptosystems, named after its inventors Rivest, Shamir, and Adleman. It uses a pair of mathematically related keys: a public key for encrypting data and a private key for decrypting it. The security of RSA relies on the difficulty of factoring very large numbers. It is commonly used for secure web communication (HTTPS), email encryption, code signing, and SSL/TLS certificate generation.

Choosing a Key Size

Key size directly affects security and performance. 1024-bit keys are considered insecure and should no longer be used. 2048-bit keys provide adequate security for most applications and are the industry standard. 4096-bit keys offer a higher security margin but are slower to generate and use. For long-term security, 4096-bit keys are recommended, while 2048-bit keys are sufficient for general-purpose encryption and signing.

Frequently Asked Questions

What is an RSA key generator?

An RSA key generator creates a pair of cryptographic keys — a public key for encryption and a private key for decryption — used in secure communications, authentication, and digital signatures.

How do I generate an RSA key pair?

Select the key size (2048, 3072, or 4096 bits) and click generate. The tool creates both the public and private keys in PEM format, ready for use in your applications.

What key size should I choose?

2048 bits is currently standard for most applications. 3072 or 4096 bits provide extra security for sensitive data. Larger keys are more secure but slower to generate and use.

What can I use RSA keys for?

RSA keys are used for HTTPS certificates, SSH authentication, email encryption (PGP/GPG), JWT signing, API authentication, and any scenario requiring asymmetric encryption.

Is this tool free?

Yes, ToolDock's RSA key generator is completely free, requires no signup, and runs entirely in your browser.

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What is RSA?

Choosing a Key Size

Frequently Asked Questions

What is an RSA key generator?

How do I generate an RSA key pair?

What key size should I choose?

What can I use RSA keys for?

Is this tool free?

Related Tools

What is RSA?

Choosing a Key Size