Random number generator, dice roller and coin flip

Pick a random number between 1 and 100, draw ten different raffle numbers from a list of 500, choose decimals between 0 and 1, roll a handful of dice or flip a coin. This random number generator does all of them on one page. Set the range, how many numbers you want, whether numbers may repeat, whole numbers or up to six decimal places, and the order, then copy the results or download them as a text file. Numbers are drawn in your browser from the cryptographic random source built into it, with no bias towards any value, and nothing is sent anywhere.

Quick answer

Enter the lowest and highest number, how many you want, and tick No repeats if each number may appear only once. Every value in the range, ends included, has the same chance. For coins or dice, switch the mode: a coin gives heads or tails with equal odds, and a die gives 1 to its number of sides.

Based on MDN Web Docs: Crypto.getRandomValues() · Page updated 17 October 2026

From

How many

Up to 10,000 at once.

Type

No repeatsEach number appears at most once, like drawing tickets from a box.

Order

Numbers are drawn in your browser with crypto.getRandomValues. Nothing is sent or stored.

Your result will appear here.

How to use the Random Number Generator

Choose Numbers, Dice or Coin flip.
For numbers, enter the range, how many you want, whole numbers or decimals, No repeats if needed, and the order.
For dice, choose how many dice and how many sides; for a coin, how many flips.
Press the button, then copy the results or download them as a .txt file.

Where the random numbers come from

The page uses crypto.getRandomValues, the random source that browsers provide for security work. MDN describes it as giving cryptographically strong random values from a pseudo-random generator seeded with enough entropy, suitable for cryptographic purposes. Turning random bits into a number in your range needs care: taking the remainder of a large random number favours small values slightly when the range does not divide it evenly. The generator avoids that by discarding draws from the uneven top block and drawing again (rejection sampling), so every value is exactly as likely as every other, even for ranges wider than four billion.

Numbers without repeats

With No repeats ticked, each value can appear only once, as if tickets were drawn from a box and not put back. You can ask for every number in a range, for example all 49 numbers from 1 to 49 in a random order to shuffle a list. If you ask for more numbers than the range holds, the page tells you rather than repeating any. Without No repeats, each draw is independent, so the same number can come up twice, just as a die can roll a six twice in a row.

Decimals, ranges and order

Choosing decimal places draws evenly from every value with that many places, so with two places between 0 and 1 there are 101 possible values from 0.00 to 1.00, both ends included. Negative ranges work too, such as −10 to 10. Sorting changes only the order in which the results are shown, not which numbers are drawn; for a draw where the order matters, such as first, second and third prize, keep the order as drawn. The sum of the numbers is shown under the list.

Dice roller and coin flip

Dice mode rolls up to 50 dice at once, each with 2 to 1,000 sides, with buttons for the common d4, d6, d8, d10, d12, d20 and d100, and shows the total. Coin mode flips a fair coin up to 1,000 times and counts heads and tails. Over a few flips the counts are often uneven; over many flips they move towards half each, which is what a fair coin does.

Using it for giveaways and classroom picks

For a giveaway, number the entries, draw with No repeats and keep a screenshot or screen recording with the settings visible, so others can see how the winner was picked. This is a free tool, not a certified draw system: where a competition, lottery or promotion must follow official rules or use an approved draw method, follow those rules.

Frequently asked questions

Is this random number generator truly random?

It uses the browser’s cryptographic random source, crypto.getRandomValues, which is strong enough for security use, and draws without bias, so no value is more likely than another. It is not a physical device, but no one can predict its results.

How do I pick random numbers without repeats?

Tick No repeats. Each number then appears at most once, so you can draw raffle numbers or shuffle a list; ask for as many numbers as the range holds to get all of them in random order.

How do I flip a coin online?

Choose Coin flip and press Flip. Each flip is heads or tails with equal odds; set more flips to see how many of each come up.

Can I roll several dice at once?

Yes. Choose Dice, set up to 50 dice and the number of sides, from 2 to 1,000. Each die is shown with the total.

Can I use it to pick a giveaway winner?

Yes for informal draws: number the entries, draw with No repeats and record the screen. For regulated competitions or lotteries, follow the method the rules require.