Random Number
Generate random numbers with range and uniqueness control.
Generate random numbers with range and uniqueness control.
Generate random numbers within a custom range with options for count and uniqueness. This free, browser-based tool is perfect for lotteries, sampling, gaming, and any situation requiring unbiased random integers. No account or installation needed.
The Random Number Generator produces one or more random integers within a specified range. You define the minimum and maximum values along with how many numbers to generate in a single draw. An optional uniqueness constraint ensures no duplicates appear in the result set, which is essential for lottery-style draws or sampling. The tool uses the browser's built-in randomization capabilities to produce unbiased results. It runs entirely client-side, meaning your selections and configurations stay private on your device.
Set the Minimum and Maximum fields to define your desired range — for example, 1 to 100. Enter how many numbers you want in the "How Many" field. Check "Unique numbers only" if you need each result to be distinct. Click "Generate" to produce your random numbers instantly. The results appear on screen and can be regenerated with a single click. Use "Clear" to reset the output and start fresh with new parameters.
Yes. The tool uses JavaScript's Math.random() function, which is a pseudo-random number generator (PRNG) that produces values uniformly distributed across the specified range. Each number in the range has an equal probability of being selected in any given draw. While all software PRNGs are technically deterministic at the lowest level, Math.random() is seeded with entropy from the operating system's random source, making it suitable for all general-purpose random selection tasks including lottery draws, sampling, and games.
If you enable "Unique numbers only" and set the count to more numbers than exist in your range (for example, requesting 15 unique numbers from a range of 1 to 10), the tool will detect this conflict and display an error message. You must either increase the maximum value, decrease the minimum value, or reduce the count to a number that fits within the range. This check prevents an infinite loop that would otherwise occur as the algorithm tried unsuccessfully to find unique values.
This tool generates integers only — whole numbers without decimal places. This is appropriate for the vast majority of use cases including lotteries, sample IDs, game values, and group assignments. If you need decimal random values (for example, a random probability between 0 and 1 or a random price point), you would need a more specialized tool or a brief calculation: take the integer result and divide by the maximum value to obtain a fraction.