Random String Generator

Generate secure, customizable random strings for passwords, tokens, and test data. 100% client-side, instant generation.

Length 16 16 characters

1 128

Character Sets

Uppercase A-Z Lowercase a-z Numbers 0-9 Symbols !@#$%

Custom Characters (optional)

Generate Count

Entropy: 0 bits

About Random String Generator

This tool generates cryptographically secure random strings using your browser's built-in random number generator (crypto.getRandomValues). No data is sent to any server. Perfect for API keys, session tokens, test data, and secure passwords.

Features

Pure client-side — strings never leave your device
Customizable length (1–128 characters) and character sets
Support for custom character sets
Batch generation — up to 50 strings at once
One-click copy and download as .txt
Multilingual support

Frequently Asked Questions

Are the generated strings secure?

Yes. We use the Web Crypto API (crypto.getRandomValues) to generate cryptographically secure random numbers. This is the same method used by modern browsers for TLS encryption.

Are strings stored anywhere?

No. Everything happens in your browser. Strings are not sent to any server and disappear when you close the tab.

What is entropy and why does it matter?

Entropy measures randomness in bits. Higher entropy means the string is harder to guess or crack. A 16-character string with all character sets has about 95 bits of entropy, which is very secure.

Can I use custom characters?

Yes. Enable the "Custom Characters" option and enter your own set of characters. The generator will only use those characters.

Random String Generator

Generated Strings

About Random String Generator

Features

Frequently Asked Questions