Random String Generator

Generate random strings in bulk from a character set of your choice

Runs in your browserUtility04Generators

What is Random String Generator?

The random string generator draws from the browser's cryptographic random source to produce batches of strings at any length, with four character sets to choose from — alphanumeric, hexadecimal, Base58 and URL-safe — and a live entropy estimate for the current settings. Everything is generated locally in your browser.

How to use Random String Generator

  1. 1Pick a character set: use the URL-safe set for values that end up in URLs, and Base58 when someone has to copy the value by hand.
  2. 2Set the length and how many strings to generate.
  3. 3Check the entropy estimate at the bottom — aim for at least 128 bits if the string will be used as an API key.

Frequently asked questions

How long should an API key be?+

Judge by entropy rather than character count, and aim for at least 128 bits. With the 62-character alphanumeric set each character carries about 5.95 bits, so 22 characters clears the bar; hexadecimal only carries 4 bits per character, so you need 32.

What is the Base58 character set for?+

Base58 removes the characters people confuse most often — 0 and O, 1 and l and I — which makes it a good fit for values that get copied by hand, read aloud or printed, such as invite codes and device identifiers. The trade-off is slightly less entropy per character, which you can make up by adding two or three more.

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