What Is a Random Number Generator?
A Random Number Generator, often shortened to RNG, produces numbers that cannot be predicted in advance. Computers are deterministic machines, so most programming languages offer pseudo-random numbers that only look random. This tool instead asks your browser for numbers from the operating system's cryptographically secure source, which is designed to be unpredictable and free of the patterns that simple generators can show.
The Number tab picks whole numbers or decimals between any minimum and maximum, one at a time or up to a thousand together, with an optional no-repeat mode that works like drawing tickets from a hat. The Dice tab rolls from one to ten dice with 4, 6, 8, 10, 12 or 20 sides, which covers most board games and tabletop role-playing games. The Coin tab flips from one to a hundred fair coins and keeps a running tally of heads and tails.
To avoid bias, the generator uses rejection sampling for whole numbers. That means every value in your range has exactly the same chance, instead of some values being slightly favored by the way a large random number is squeezed into a small range.
How to Use the Random Number Generator
- Pick a tab: Number for ranges, Dice for game rolls or Coin for heads or tails.
- On the Number tab, enter the minimum and maximum, and choose how many numbers you want.
- Switch between whole numbers and decimals, and tick No repeats if each result must be different.
- Press Generate, Roll Dice or Flip Coin. The result appears instantly.
- On the Number tab, press Copy Result to copy the list to your clipboard.
- Press the button again whenever you want a new set of results.
Key Features of Our Random Number Generator
- Whole numbers or decimals with up to 10 decimal places
- Generate up to 1,000 numbers at once with sum and average
- Unique mode that never repeats a value
- Dice roller for d4, d6, d8, d10, d12 and d20 with up to 10 dice
- Coin flipper with up to 100 flips and a heads and tails tally
- Secure randomness from the Web Crypto API with unbiased range handling
- Clear error messages for impossible ranges or too many unique numbers
- Free to use with no sign-up and no limits
Benefits of Using an Online Random Number Generator
Fair choices matter when people are watching. A visible, unbiased random draw settles who goes first, which raffle ticket wins or who presents next, and nobody can argue that the pick was rigged.
Because the tool combines three utilities in one page, you do not need separate apps for a game night, a class activity or a quick decision. It works on any phone or computer with a modern browser.
Your privacy comes first. The Random Number Generator runs entirely in your web browser. Nothing you enter is sent to our servers, which keeps your data private and makes results appear instantly. See our Privacy Policy for details.
Common Use Cases for the Random Number Generator
- Picking raffle or giveaway winners from a numbered list
- Rolling dice for board games and tabletop role-playing games when you have lost the dice
- Choosing who goes first with a coin flip
- Creating random sample numbers for classroom statistics lessons
- Selecting random rows or participants for surveys and research
- Generating test data and sample values while developing software
- Drawing lottery-style number sets with no repeats
- Settling friendly disagreements quickly
Tips for Getting the Best Results
- For a giveaway, number your entries from 1 to the total and generate one unique number so the draw is easy to verify on screen.
- Record the date, range and result if you need proof of a fair draw, and consider sharing a screenshot.
- Remember that random does not mean evenly spread. Streaks such as five heads in a row are normal over many flips.
- Use unique mode when picking several winners so the same entry cannot be drawn twice.
- For decimals, set the number of decimal places to match what you need, such as 2 for prices.
- To simulate multiple dice such as 3d6 for tabletop games, set three dice with six sides and read the total.
Random Number Generator FAQ
Is this Random Number Generator truly random?
It uses your browser's cryptographically secure random source, which is suitable for fair draws and unpredictable results. It is far better than the basic Math.random function that many simple generators rely on.
Can I generate numbers without repeats?
Yes. Tick No repeats on the Number tab. The tool will refuse if you ask for more unique numbers than the range contains, for example 20 unique numbers between 1 and 10.
Are the minimum and maximum included?
Yes. For whole numbers both limits can appear in the results. For decimals, results fall between the limits and are rounded to your chosen number of places.
Can I use this for a legal lottery or gambling?
It is fine for informal draws and games. Regulated lotteries and gambling have their own rules and certified equipment, so check your local requirements.
How many dice can I roll?
Up to ten at a time, each with 4, 6, 8, 10, 12 or 20 sides. The total is calculated for you.
Does the tool remember my results?
No. Results exist only on your screen and are cleared when you leave or refresh the page. Nothing is sent to a server.