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Random String Generator

Generate random strings in bulk from whichever alphabet you need — plain letters and numbers, hex for keys and colours, URL-safe characters for slugs and tokens, or a custom set you type yourself. Add a prefix and you get identifiers shaped like the ones your system already uses. Everything is produced in the browser, so a hundred strings appear the instant you ask for them.

24
10

Only used when the alphabet above is set to Custom. Repeated characters make themselves more likely.

Added to the front of every string. It doesn't count toward the length.

Result

10 strings of 24 characters from a 62-character alphabet — about 143 bits each. The seed makes this list reproducible, so don't use these as API keys or session tokens.

Nothing is uploaded — this tool runs inside your browser, so your files never leave your device.

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Why use this tool

  • Up to 100 strings at a time, 1 to 128 characters each
  • Letters, numbers, hex, URL-safe or a custom alphabet
  • Optional prefix, for identifiers shaped like sk_test_ or user_
  • Warns you when the length is short enough that strings start repeating

How it works

  1. 1Pick an alphabet, or choose Custom and type the characters you want.
  2. 2Set the length and how many strings you need.
  3. 3Copy the list, or download it as a text file.

Random String Generator — frequently asked questions

No. The strings are derived from the seed number so the list can be reproduced, which is useful for test fixtures and fatal for a secret. Generate anything that must be unguessable where it is used, from a cryptographic source: crypto.getRandomValues in the browser, crypto.randomBytes in Node, secrets.token_urlsafe in Python.

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