Random String Generator

Runs in browser Utilities

Produce one or many random strings from letters, digits, symbols, hex or a custom alphabet, with optional prefixes and exclusion of look-alike characters.

Privacy: This tool runs entirely in your browser. Your input never leaves your device.

How to use Random String Generator

  1. Set the length and how many strings you need.
  2. Choose a character set or type your own alphabet.
  3. Generate, then copy one line or download the whole list.

Random String Generator features

  • Cryptographically secure randomness (crypto.getRandomValues)
  • Letters, digits, symbols, hex, base32, base64url or a custom alphabet
  • Exclude look-alike characters (0 O 1 l I)
  • Prefix, quantity up to 1,000 and uniqueness guarantee
  • Entropy estimate with guidance for identifiers vs secrets

Random String Generator example

Five API-style tokens

Input:

Length 24 · letters & digits · prefix tok_

Output:

tok_H7qK2mZp9vX4cR8wN1bL3sYt
tok_a9Fd4Jk1Qw7Er2Ty5Ui8Op0A
… (142.7 bits of entropy each)

Frequently asked questions about Random String Generator

Is the output cryptographically secure?

Yes. Characters are drawn with crypto.getRandomValues, the browser's CSPRNG, so the strings are suitable for tokens, nonces and temporary secrets.

What does the entropy figure mean?

Bits of randomness per string: length × log2(alphabet size). Aim for 128 bits or more for secrets; 64 bits is fine for identifiers.

What are look-alike characters?

Characters that are easy to confuse when read or typed: 0/O, 1/l/I and the quote characters. Excluding them is useful for codes people must read aloud or type.

Can I use my own alphabet?

Choose "Custom alphabet" and enter the characters to use — Unicode letters and emoji are allowed. Duplicate characters are ignored.