🎲 Random String Generator
Generate cryptographically random strings for tokens, IDs, passwords, and more.
About This Random String Generator
What It Does
This tool generates cryptographically random strings using your browser's built-in Web Crypto API (crypto.getRandomValues). Unlike Math.random(), which is predictable, the Web Crypto API draws from your operating system's entropy pool — the same randomness source used for SSL/TLS encryption keys. Each generated character is selected by taking a random byte modulo the character set size, ensuring uniform distribution across your chosen alphabet. You control the length, count, and character composition, and everything happens client-side — no data is ever sent to a server.
Features
- Generate 1 to 50 random strings at once
- Configurable length from 1 to 2048 characters
- Toggleable character sets: uppercase (A-Z), lowercase (a-z), digits (0-9), and symbols
- Five one-click presets: API Token (32 chars), Short ID (12), Hex Color, PIN Code (6), URL Slug (8)
- Cryptographically secure — uses crypto.getRandomValues(), not Math.random()
- One-click copy of all generated strings
Common Use Cases
Developers generate API tokens for service authentication — 32-character alphanumeric strings are standard for bearer tokens. Short IDs are used as user-facing identifiers in URLs (like YouTube video IDs or Bitly shortlinks) where a full UUID would be unwieldy. PIN codes at 6 digits are common for two-factor authentication and temporary access codes. URL slugs at 8 lowercase characters produce clean, readable paths for blog posts and product pages. Hex colors are used by designers grabbing quick palette values for CSS and design tools.
Tips
For password generation, enable all four character sets (uppercase, lowercase, digits, symbols) and use at least 16 characters. For API tokens, the default 32-character alphanumeric preset hits the sweet spot between security and practicality. Generate multiple strings at once when you need to seed a database with test data or create a batch of invite codes. The hex color preset ignores your character set selections and always produces 7-character hex codes (# plus 6 hex digits).
FAQ
How random are these strings really?
They're cryptographically random — the same quality of randomness used to generate SSL certificates and encryption keys. crypto.getRandomValues() draws from /dev/urandom on Linux, which gathers entropy from hardware interrupts, disk timing, and mouse/keyboard activity. For all practical purposes, these strings are unpredictable and unique.
Can I use these as passwords?
Yes, with the right settings. Enable all four character sets and generate at least 16 characters. A 16-character string from an 89-character alphabet has about 105 bits of entropy — more than enough for any online account. Store the result in a password manager rather than trying to memorize it.
What's wrong with Math.random() for generating tokens?
Math.random() is a pseudorandom number generator (PRNG) designed for speed, not security. Its internal state can be predicted after observing enough outputs, and most browsers use algorithms like xorshift128+ that are not cryptographically secure. An attacker who can predict your random tokens can hijack sessions, reset passwords, or forge API keys. Always use crypto.getRandomValues() for anything security-related.
Can I generate UUIDs with this?
UUIDs have a specific format (xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx with version and variant bits). Use our dedicated UUID Generator for standards-compliant UUIDs. This random string generator produces arbitrary-length strings with your chosen character sets — better for tokens, IDs, and passwords.