Random number generator.

How to generate random numbers in 3 steps

1. Set the range. Type the smallest and largest number you want, or tap a quick range: 1–10, 1–100 or 1–1,000. Negative numbers and numbers up to nine digits work too.
2. Say how many. One number rolls in like a counter. Ask for up to 100 and they appear as a list. No repeats is on, so a number can’t come up twice in one draw; turn it off if repeats are fine. Sort low to high puts the list in order.
3. Press Generate, or the Space bar. Press Copy to put the numbers on your clipboard, comma separated, ready for a spreadsheet or a message.

The last 10 draws stay under the tool with their range, each with its own copy button. Press F or Full screen to show a draw on a projector or a TV. Esc brings you back.

Is it really random?

Yes. Every number comes from your browser’s cryptographic random source, the same one websites use to make security keys. The tool throws away the few raw values that would make low numbers slightly more likely, so each number in your range has exactly the same chance. No draw remembers the one before it.

With no repeats on, a small range is shuffled and the first numbers taken, like dealing cards. A huge range is drawn number by number, skipping any repeat. Either way, every set of numbers is equally likely.

Ideas for events, classes and everyday picks

• Raffles at events. Sold tickets 1 to 300? Set the range, ask for as many winners as there are prizes, and leave no repeats on so no ticket wins twice. Full screen lets the hall watch the draw.
• Pick a student number. Number the class list and draw one to answer, or draw five to form a panel. Nobody can say you chose them on purpose.
• Pick a question number. Worksheets, past papers, flash cards: draw a number and that is the question the class works through together.
• A random page or row. Open a book at a random page for a reading check, or pick a random row from a spreadsheet to spot-check the data.
• Random order. Draw 1 to 12 with no repeats and sort off: that is the order the twelve speakers present in.
• Maths and statistics. Draw a sample of 10 from 1 to 1,000 and compare it with the next sample. Good for a first lesson on sampling, ages 13 and over.

Draw the winner where everyone can see

A list of numbers is quick. A wheel is a show. For a prize draw in front of a room, the random number wheel spins the same fair draw with every number on a slice. To draw names rather than numbers, the random name picker wheel takes your list.

When the audience is in the room with their phones, run the draw live in RiLiFi: the live spinning wheel shows the spin on the big screen and keeps every winner. Free for 100 people in each session.