Skip to content

Tools

EN

Random Number Between 1 and 100

The range is already filled in. Press the button. Change how many you want, or turn on “no repeats” if the same number must not come out twice.

What 1 to 100 is usually for

One to a hundred is the range people reach for when they want a draw that feels wide enough to be fair but small enough to say out loud. It is the classroom number-guessing game, the tiebreaker where everyone picks a number and the closest wins, the raffle where tickets were numbered by hand. A hundred is also the size at which a person can hold the whole range in their head, which is exactly why guessing games use it and why 1 to 1,000 feels arbitrary by comparison.

If you are running a draw where the same number must not come out twice, turn on “no repeats”. Drawing five numbers from 1 to 100 with repeats allowed gives you a duplicate about one time in ten: the birthday problem in miniature, and much more often than people expect. With repeats off, each number is pulled out and set aside, so five draws give five different numbers.

For the guessing game, one number and a closed hand is the whole setup: draw, do not look at the screen, and let the other person work down from fifty. Seven guesses are always enough if they halve the range each time, which is a pleasant thing to discover and a decent way to explain binary search to somebody who has never heard of it.

The draw itself is the same one behind every range on this site: values come from the browser’s cryptographic generator, and the ones that would not divide evenly into a hundred are discarded rather than folded back in. That last step is what keeps 1 to 96 from coming up very slightly more often than 97 to 100, a small unfairness that most generators still have and that nobody notices until they are counting.

Frequently asked questions

Is 1 to 100 inclusive of both ends?

Yes. Both 1 and 100 can come out, and each has exactly the same chance as every number in between.

How do I stop the same number appearing twice?

Tick “no repeats” and raise the count. Each number is then drawn at most once, like tickets pulled from a hat and kept out. With a hundred numbers you can draw up to a hundred that way.

Can I use a different range?

Change the two fields, or use the general random number generator, which starts empty and takes any range you like.

Why did I get the same number twice in a row?

Because draws are independent: the generator has no memory of the last result, so the chance of repeating it is one in a hundred, the same as any other specific number. Over many draws that happens exactly as often as it should.

Other tools