What key sizes are available?

The tool generates 1024-bit (development/testing only), 2048-bit (standard), and 4096-bit (high security) RSA key pairs.

Is the private key safe?

Yes. Key generation uses the browser's Web Crypto API. The private key is generated locally and never sent anywhere.

What formats are the keys exported in?

Public and private keys are exported in PEM format (PKCS#8 for private keys, SPKI for public keys) compatible with OpenSSL and most crypto libraries.

Best Free Online RSA Key Generator

RSA key pairs are required for asymmetric encryption, JWT RS256 signing, SSH authentication, TLS certificates, and many other security workflows. devtoolkit.sh's RSA Key Generator creates key pairs of 1024, 2048, or 4096 bits entirely in your browser using the Web Crypto API — your private key is generated locally and never transmitted anywhere. The output is formatted in PEM (PKCS#1 or PKCS#8) for immediate use with OpenSSL, Node.js, Python, Java, and most cryptographic libraries. This is ideal for generating test keys during development, creating keys for JWT signing, and learning how RSA key structure works without installing OpenSSL locally.

Key size:

FAQ

What key sizes are available?: The tool generates 1024-bit (development/testing only), 2048-bit (standard), and 4096-bit (high security) RSA key pairs.
Is the private key safe?: Yes. Key generation uses the browser's Web Crypto API. The private key is generated locally and never sent anywhere.
What formats are the keys exported in?: Public and private keys are exported in PEM format (PKCS#8 for private keys, SPKI for public keys) compatible with OpenSSL and most crypto libraries.