Random Number Generator
Pick random integers or decimals between a minimum and maximum, optionally with no duplicates.
How to use the Random Number Generator
- Enter the minimum.
- Enter the maximum.
- Enter the how many numbers.
- Choose the type.
- Enter the decimal places.
- Choose the repeats.
- Tick Sort the results if it applies.
- Press Calculate. The result updates automatically as you type.
About the Random Number Generator
Use this generator to pick raffle winners, assign random groups or seating, choose a random sample from a numbered list, roll virtual dice (1 to 6) or settle a decision fairly. Both ends of the range are included for whole numbers, so 1 to 100 can return either 1 or 100.
When available, numbers come from your browser's cryptographic random source (Web Crypto), which is much less predictable than an ordinary pseudo-random function; otherwise standard JavaScript randomness is used. Everything runs on your device and nothing is sent or stored. For official lotteries, legal drawings or security keys, follow the rules and certified tools those situations require.
Formula
Whole numbers: n = min + ⌊U × (max − min + 1)⌋ Decimals: n = min + U × (max − min)
U is a uniform random value from 0 (inclusive) up to 1 (exclusive). For unique draws the generator simply redraws any value it has already produced, so every remaining number stays equally likely.
Example
With the default range of 1 to 100, each press of Calculate picks a new whole number between 1 and 100, where every value has the same 1% chance.
Frequently asked questions
Are the numbers truly random?
They come from your browser's cryptographically secure generator when available, which is unpredictable enough for games, sampling and everyday draws.
How do I simulate a dice roll?
Set the minimum to 1, the maximum to 6, choose whole numbers and allow repeats. Set "How many" to the number of dice.
Can I generate lottery-style numbers?
Yes. For example, choose 1 to 69, five numbers, no repeats, and sort the results.
Last updated: · Category: Math calculators