RSA Key Pair Generator Online — Free & Private

A free edge API by formatho.com, privacy-first developer tools.

Free, no signup, runs entirely in your browser — your data never leaves your device.

🔓 Free🔒 Zero tracking🚫 Keys never stored⚡ Edge-fast

Usage

# Generate a 2048-bit RSA key pair (default)
curl "https://rsa-key-pair-generator-formatho.filesformatho.workers.dev/api"

# 4096-bit key pair with OpenSSH public key + fingerprints
curl "https://rsa-key-pair-generator-formatho.filesformatho.workers.dev/api?bits=4096"

# JWK format instead of PEM
curl "https://rsa-key-pair-generator-formatho.filesformatho.workers.dev/api?bits=2048&format=jwk"

Returns the private key as PKCS#8 PEM, the public key as SPKI PEM plus an OpenSSH-style ssh-rsa line and SHA-256/SHA-512 public-key fingerprints, with the verified modulus size in bits.

Full parameter reference: /api endpoint.

Privacy-first: keys are generated in-memory at the edge for your request only — never cached (Cache-Control: no-store), never logged, never stored.

Use for development and testing. For production systems, generate keys client-side (the full browser tool below does exactly that) or in your own infrastructure — never route production private keys through any third-party service.

Full browser tool

Generate keys entirely client-side in your browser: RSA Key Pair Generator on formatho.com.

All Formatho edge APIs

Browse every free Formatho Worker tool on the Formatho Tools index.