RSA Key Generator: what it does and how to use it

RSA is a widely-used public-key cryptography algorithm - you generate a linked key PAIR (public and private), where data encrypted with the public key can only be decrypted with the private key, and vice versa for signing. This tool generates RSA key pairs and exports them in standard PEM format, ready to use in code or configuration.

Anything that hashes, generates keys or checks a password should stay on your machine. If a site asks you to upload a secret, close the tab.

RSA Key Generator is a good fit when preparing key pairs for JWT RS algorithms in staging.

The useful part

RSA Key Generator is built around a few practical wins, not a long feature list:

• Quickly generates standards-compliant RSA PEM key pairs.
• Useful for API auth, certificates, and signature workflows.
• Saves setup time in development and testing environments.
• Helps teams understand public/private key separation clearly.

Do this, in order

1. Choose key length. Select 2048/4096-bit according to security policy and performance target.
2. Generate RSA key pair. Create linked public/private PEM outputs for signing or encryption.
3. Export and store securely. Copy/download keys and protect private key using secure secret storage.
4. Validate integration. Test encryption/decryption or sign/verify flow in target environment.

Who it is for

• Preparing key pairs for JWT RS algorithms in staging.
• Testing signature verification between services.
• Creating temporary keys for CI or integration demos.
• Learning asymmetric cryptography operational workflow.

If you want a clean result

• Protect private keys with strict access controls and rotation policy.
• Use passphrase-protected private keys where possible.
• Prefer generating long-term prod keys inside controlled infra/HSM.
• Track key IDs and issuance dates for lifecycle management.

Common mix-ups

• Committing private keys to repository history.
• Using weak or outdated key sizes in production systems.
• Confusing encryption use with signing use without protocol design.
• Sharing private key over insecure communication channels.

Private by default

RSA Key Generator runs in your browser. The file or text you paste stays on your device. There is no account, and nothing is stored on a ToolBox server for this job.

Related tools worth opening next

If this is one step in a longer job, these usually come after it:

• JWT Generator - Create and sign JSON Web Tokens with HS256/384/512
• JWT Encoder - Encode and sign JWTs with HS/RS/ES/PS algorithms in the browser
• Password Generator - Generate strong secure passwords

Before you ask

What's the difference between the public and private key?

The public key can be shared freely - others use it to encrypt data meant only for you, or verify signatures you created. The private key must be kept secret - you use it to decrypt data encrypted with your public key, or to create digital signatures.

Is it safe to generate keys for real production use here?

Key generation runs in your browser using standard cryptographic APIs, but for genuinely sensitive production systems, many teams prefer generating keys directly on the target server/environment using established tooling (like OpenSSL) to minimize any exposure during transfer.

What key size should I choose?

2048-bit is a common modern minimum for RSA keys; 4096-bit offers a larger security margin at the cost of slower performance - check what your specific use case or compliance requirement expects.

Open the RSA Key Generator when you are ready. It is free, and you do not need an account.