Random Number Generator

What is a random number generator and why use one?

A random number generator (RNG) produces numbers that cannot be predicted in advance. It is the digital equivalent of drawing a number from a hat, rolling dice or flipping a coin. People use it for everything from classroom activities and party games to prize draws, board games and quick decision-making. Our generator runs entirely in your browser — no server calls, no waiting, no logs.

How the random number generator works

We use your browser's built-in Math.random() function, which returns a floating-point number between 0 (inclusive) and 1 (exclusive). To turn that into a random integer in a custom range [min, max], the formula is:

The ⌊ ⌋ symbol means "round down to the nearest integer". When you ask for multiple numbers, the process repeats independently each time. Each number has an equal probability of landing anywhere in the range you set.

Step-by-step: pick a random number

1. Enter a minimum value. The smallest number you want to include — for example 1.
2. Enter a maximum value. The largest number you want to include — for example 100. Make sure max ≥ min.
3. Choose how many numbers. Set to 1 for a single pick, or higher to generate a list. Duplicates are allowed when generating multiple numbers, just like drawing with replacement.
4. Click Generate. Your random number(s) appear instantly above.

Practical examples

• Prize draw: 500 raffle tickets numbered 1–500. Generate 1 random number between 1 and 500 to pick the winner.
• Classroom roll call: 36 students in a class. Generate numbers between 1 and 36 to randomly select who answers next.
• Password pins: Generate 6 numbers between 0 and 9 for a 6-digit verification code (note: not for high-security use).
• Decision making: Letting the RNG decide between option 1 and 2 is a fair way to break a tie.

Dice roller — how it works

The built-in dice roller simulates a standard 6-sided die (D6). Each face (⚀⚁⚂⚃⚄⚅) appears with equal probability, exactly like a physical die. It is perfect for board games when you do not have dice handy, or for online play with friends.

For different die types (D4, D8, D10, D12, D20), simply use the random number generator above and set the range accordingly — for a D20, set min=1 and max=20.

Is Math.random() secure?

No. Math.random() is a pseudo-random generator — it is fast and well-distributed for everyday use, but its output is technically predictable to a determined attacker. It is completely fine for games, draws, teaching and casual decisions. For cryptographic purposes (secure keys, passwords, tokens), use window.crypto.getRandomValues() or a dedicated library instead.