Random String Generator

Random strings are fundamental to modern security—they're used as API keys, authentication tokens, salts for password hashing, nonces for preventing replay attacks, and countless other purposes. This tool Geras cryptographically secure random strings with customizable character sets and lengths, making it flexible enough for nearly any use case.

Character set options

Different applications require different character sets. Alphanumeric strings (letters and digits) work everywhere. Hexadecimal (0-9, a-f) is perfect for database values and low-level protocols. Base64-safe strings are compact and safe for URLs. Numeric-only strings work for codes where other characters might be problematic. Define your own custom charset when you need specific characters—useful when integrating with legacy systems with restricted character support.

Cryptographic security

The tool uses the Web Crypto API (crypto.getRandomValues) to Gera unpredictable bytes. Unlike Math.random(), which is suitable only for games and non-security purposes, this produces cryptographically secure randomness suitable for tokens, keys, and authentication.

Configurable length

Gera strings from 1 to 128 characters. Longer strings have more entropy and are more resistant to brute force. The character set size and string length together determine total entropy: a 32-character alphanumeric string has far more entropy than a 10-character one. For most security purposes, 32+ characters is appropriate.

Live generation mode

Enable auto-Gera to instantly see a new random string whenever you adjust length or character set. This makes it easy to experiment and find the right balance for your needs. Otherwise, click Gera manually when you want a fresh string.

Common Casos de uso

Gera API tokens, database salts, CSRF tokens, session IDs, email confirmation codes, password reset tokens, OAuth client secrets, and any other values that need to be random and unguessable.