Is this generator truly random and secure?

Yes. Keys are generated using window.crypto.getRandomValues(), which is backed by the operating system's cryptographically secure pseudorandom number generator (CSPRNG). This is suitable for production use.

Which AES key size should I use?

AES-256 is the most widely recommended for new projects, offering the highest security margin. AES-128 provides strong security with slightly faster performance. AES-192 is rarely used in practice.

Are my generated keys stored or sent anywhere?

No. All key generation happens entirely in your browser using the Web Crypto API. Nothing is sent to any server. Close the tab and the key is gone — save it somewhere secure immediately.

What is the difference between hex and Base64 output?

Both represent the same raw key bytes in different encodings. Hex uses 0-9 and a-f characters (2 chars per byte). Base64 uses a 64-character alphabet and is more compact. Use whichever format your target library expects.

Can I use these keys directly in code?

Yes. Copy the hex string and pass it to your crypto library (e.g., Node.js crypto.createCipheriv), or use the Base64 value with libraries that accept Base64-encoded keys. Always store keys in environment variables or a key management service, never hard-coded.

AES Encryption Key Generator

Generate cryptographically secure AES-128, AES-192, or AES-256 keys instantly in hex and Base64 formats using your browser's Web Crypto API.

Key Settings

Key Size

Keys are generated locally using window.crypto.getRandomValues() — a browser CSPRNG. Nothing is sent to any server.

Generated Key

Choose a key size and click Generate Key

Copied!

Summary

This tool generates cryptographically secure AES encryption keys of 128, 192, or 256 bits directly in your browser using the Web Crypto API. Keys are never sent to any server — all generation happens client-side. The output is provided in both hexadecimal and Base64 encodings for easy integration into your application.

How it works

Select the desired AES key size: 128-bit, 192-bit, or 256-bit.
Click "Generate Key" — the browser calls window.crypto.getRandomValues() to produce a cryptographically secure random byte sequence.
The key is displayed in both hexadecimal and Base64 formats.
Click the copy button next to either format to copy the key to your clipboard.
Click "Generate Key" again to produce a fresh key at any time.

Use cases

Generate AES keys for symmetric encryption in backend services.
Create secret keys for JWT HS256/HS384/HS512 signing.
Produce keys for encrypting sensitive data at rest.
Generate master keys for password-derived key stretching (PBKDF2, scrypt).
Quickly test AES encryption implementations with known key sizes.
Create keys for client-side encryption using SubtleCrypto.

Frequently Asked Questions

Last updated: 2026-10-03 · Reviewed by Nham Vu