Random Number Generator

Generate cryptographically random numbers in any range. Set min, max, quantity, optional uniqueness and sorting. Presets for dice, coins, lottery.

tuneSettings

boltQuick Presets

What is the Random Number Generator?

A random number generator picks integers from a range you define. The good ones use a cryptographically secure source (like crypto.getRandomValues) instead of Math.random, which means the output isn't predictable from past values. Useful for picking winners, simulating dice, sampling from a list, or anything where bias would matter.

How to use the Random Number Generator

  1. 1

    Set the range

    Type the minimum and maximum values in the sidebar. Negative numbers and large ranges both work.

  2. 2

    Pick how many you want

    The Quantity field controls how many numbers come out per click, up to 1000.

  3. 3

    Toggle options if needed

    No duplicates samples without replacement (good for lotteries). Sort results arranges the output ascending.

  4. 4

    Click Generate

    The numbers appear as cards. Click Generate again for a fresh draw, or Copy to send the comma-separated list to your clipboard.

Frequently Asked Questions

Are the numbers truly random?

They're drawn from crypto.getRandomValues, the browser's cryptographically secure random source. That's the same primitive used for session tokens and HTTPS handshakes, and it's resistant to prediction even if you know previous outputs. Don't confuse it with Math.random, which is fast but not safe for anything adversarial.

Can I avoid duplicate numbers?

Toggle the No duplicates option. The generator then samples without replacement from your range, like drawing balls from a lottery cage. If you ask for more numbers than the range contains, you'll get fewer than requested (since duplicates aren't allowed).

What are the quick presets?

Three: Dice (one number from 1 to 6), Coin Flip (one number from 0 to 1), and Lottery (six unique numbers from 1 to 49, the standard for a UK Lotto draw). Each preset overwrites the min/max/qty fields so you can roll instantly.

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