How to use the random number generator
Set the lowest and highest values you want, choose how many numbers to draw and whether you need whole numbers or decimals, then press Generate. Each press produces a fresh result. Tick "No duplicates" to draw unique numbers, as you would for a raffle, a lottery-style draw or picking a random sample of people from a numbered list. Large lists can be copied with a single click.
How random are the numbers?
Many simple tools use a pseudo-random algorithm such as JavaScript's Math.random(), which is fine for games but predictable in principle. This generator uses the Web Crypto API (crypto.getRandomValues), the same cryptographically secure source browsers use to generate encryption keys. To avoid "modulo bias" – where some numbers come up slightly more often when the range doesn't divide evenly into the generator's output – values outside a fair range are discarded and redrawn. Every whole number in your range therefore has exactly the same chance of appearing.
Unique draws
With "No duplicates" on, each number can appear only once, like drawing numbered balls from a bag without putting them back. The count must not exceed the number of whole numbers available in the range – you can't draw 10 unique numbers between 1 and 5.
Ideas for using random numbers
- Pick a giveaway winner from a numbered list of entries.
- Assign people to teams or decide turn order in a game.
- Choose a random sample for a survey or quality check.
- Create practice data or test values for spreadsheets and software.
- Roll virtual dice: set the range to 1–6.
All numbers are generated locally in your browser; nothing is logged or sent to a server, so results cannot be influenced or recorded by us.
Worked example
Imagine 250 people entered a giveaway and you want three winners. Set the minimum to 1, the maximum to 250, ask for 3 numbers and tick "No duplicates". Each press of Generate gives three different entry numbers, each with exactly the same 1-in-250 chance of being picked.
Frequently asked questions
Is this random number generator truly random?
It uses your browser’s cryptographically secure random source, which is unpredictable and suitable even for security purposes.
How do I generate numbers without repeats?
Tick "No duplicates". Each whole number in the range can then appear at most once.
Can I generate negative or decimal numbers?
Yes. Enter a negative minimum if needed, and choose "Decimals" with the number of decimal places you want.
Can I use it for a giveaway?
Yes. Number your entries, set the range to match and draw one or more unique numbers. Consider recording your screen for transparency.
Last reviewed 2026-10-27. This random number generator is provided for general information; verify important decisions with a qualified professional.