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Random Number Generator

Choose a minimum and a maximum, then press Generate Number to pick one whole number in that range.

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Random Number Generator generates numbers in your browser.

Pick a random whole number

Choosing who goes first, picking a question number, settling a tie, or drawing a number for a classroom game: set a minimum and a maximum, press Generate Number, and one whole number from that range appears. Both ends are included, negative numbers work, and every number in the range has the same chance. Press Generate Again for a fresh number from the same range.

How to use the Random Number Generator

  1. Enter the minimum and the maximum as whole numbers. They start at 1 and 100; the maximum must be at least the minimum.
  2. Press Generate Number. Nothing is drawn until you press it.
  3. Press Generate Again for another number, Copy Result to copy it, or Reset to go back to 1 to 100. Changing the range clears the previous number.

How the number is chosen

numbers in range = maximum − minimum + 1

result = minimum + (random draw mod numbers in range)

draws at or above the largest multiple of the range size are discarded and redrawn

Each draw takes 53 random bits from your browser’s crypto.getRandomValues(). Taking the remainder of a random draw on its own would make the lowest numbers in the range very slightly more likely (modulo bias), so any draw that falls in the final, incomplete block of the range is thrown away and replaced. What remains maps evenly onto the range, so each number has exactly the same chance: 1 in N for a range of N numbers, which the Percentage Calculator can turn into a percentage (1 in 20 is 5%).

Range sizes and the chance of each number
RangePossible numbersChance of each
1 to 661 in 6
1 to 10101 in 10
1 to 1001001 in 100
0 to 991001 in 100
-10 to 10211 in 21
7 to 711 in 1

Generated on your device

  • Numbers are generated in your browser; nothing is sent to a server.
  • Your range and the numbers drawn are not sent to Looty Tools or stored.
  • The generator area is masked from session-recording analytics, so what you enter and draw isn’t captured in recordings.

Limitations

  • One whole number per press. It doesn’t draw lists, unique sets without repeats, decimals, or dice rolls.
  • Not for passwords, security keys, lotteries, gambling, or anything where a draw must be audited or provably fair.
  • Minimum and maximum must be whole numbers from −1,000,000,000,000,000 to 1,000,000,000,000,000.
  • Each press is independent, so the same number can come up twice in a row.

Related tools

Random Number Generator FAQ

Are the minimum and maximum included?
Yes. A range of 1 to 100 can produce 1, 100, or any whole number between — 100 possible numbers in all.
Is every number equally likely?
Yes. The generator draws 53 random bits and throws away the rare draws that would favor the low end of the range (modulo bias), so each number has exactly the same chance.
Where does the randomness come from?
From your browser’s built-in crypto.getRandomValues() function, which is backed by the operating system’s random-number source.
Can I use negative numbers or a very large range?
Yes. Both ends can be negative, and whole numbers up to 1,000,000,000,000,000 either side of zero are accepted. If the minimum and maximum are the same, that number is the result.
Can I use it for passwords, lotteries, or gambling?
No. It is an everyday tool for things like picking a number for a game or a classroom. Use purpose-built tools for passwords and security keys, and official systems for lotteries, raffles with rules, or anything involving money.
Does it pick a number when the page opens?
No. A number is only drawn when you press Generate Number, and each press of Generate Again draws a fresh one.
Are my range and results sent anywhere?
No. Numbers are generated in your browser. The range and the results are not sent to Looty Tools or stored, and the generator area is masked from session-recording analytics.

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