# RSA & ECDSA Key Pair Generator

> Generate an RSA or elliptic-curve key pair in your browser, exported as PEM or JWK.

This generates an RSA, ECDSA or Ed25519 key pair using your browser's WebCrypto API and exports it as PEM or JWK. ECDSA with P-256 gives the same 128-bit security as RSA-3072 in a fraction of the size, which is why it is the better default for anything new.

**URL:** https://convertto.tech/t/keypair-generator
**Category:** Hash & Crypto Tools (https://convertto.tech/c/crypto-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Generated by:** The browser's WebCrypto API, using the OS cryptographic random source
- **Never transmitted:** The private key exists only in this page's memory
- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Choose the algorithm.
2. Choose the curve.
3. Choose the key size.
4. Choose the purpose.
5. Choose the export as.
6. Press Run, then download the result when it is ready.

## FAQ

### Is it safe to generate keys in a browser?

WebCrypto uses the same OS random source as command-line tools, so the key itself is sound. The risk is the surrounding environment — browser extensions, screen capture and clipboard history all see the page. For a production key, use ssh-keygen or openssl on the target machine.

### RSA or elliptic curve?

Elliptic curve, for anything new. ECDSA P-256 matches RSA-3072 for security while being roughly a tenth the size and far faster to generate. Choose RSA only when you must interoperate with something that cannot do EC.

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