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RSA Key Generator

Generate 2048, 3072, or 4096-bit RSA key pairs locally. Choose signing or encryption, then copy the public SPKI and private PKCS#8 keys in PEM format.

🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.

How RSA Key Generator works

  1. Choose 2048, 3072, or 4096 bits.
  2. Select Sign / verify or Encrypt / decrypt, then generate the key pair.
  3. Copy the public and private PEM outputs with their separate copy buttons.

FAQ

Which RSA key sizes can I generate?

The selector offers 2048, 3072, and 4096 bits.

What PEM formats does the generator output?

The public key uses SPKI with a PUBLIC KEY label. The private key uses PKCS#8 with a PRIVATE KEY label.

What is the difference between the usage options?

Sign / verify generates keys using RSASSA-PKCS1-v1_5. Encrypt / decrypt uses RSA-OAEP. Both options use SHA-256 in the Web Crypto configuration.

Are RSA keys generated on a server?

No. Generation and export use the browser Web Crypto API locally. Copy buttons place the selected PEM output on your clipboard.

Available features

FeatureOnline Tool Store
Three RSA key sizes
SPKI and PKCS#8 PEM output
Separate public and private key copy buttons

Features listed here are available in the current browser widget.

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