Generate truly random integers or decimals within any range. Choose between a simple single-number generator and a comprehensive version that supports multiple outputs, decimal precision, and very large numbers.
How to use this calculator
Enter lower and upper limits, then click Generate. The simple generator creates a single random integer. The comprehensive version supports multiple numbers, decimal output, and custom precision. Clear resets the inputs while keeping the last result.
Generates a single random integer. Supports very large integers up to a few thousand digits.
Result
33
Frequently Asked Questions
Generate one or many integers or decimals. Supports up to 999 digits of precision.
Result
39.62114610402863235094628180377185344696044921875000
About Random Number Generators
A random number is a number chosen from a pool of limited or unlimited numbers that has no discernible pattern for prediction. The pool of numbers is almost always independent from each other. However, the pool of numbers may follow a specific distribution — for example, the height of students in a school tends to follow a normal distribution around the median height.
A random number generator (RNG) is a device that generates one or many random numbers within a defined scope. RNGs can be hardware-based or pseudo-random. Hardware-based generators use physical phenomena such as dice rolls or coin flips. Computer-based generators are almost always pseudo-random number generators (PRNGs).
A pseudo-random number generator is an algorithm for generating a sequence of numbers whose properties approximate the properties of sequences of truly random numbers. The random numbers generated are sufficient for most applications, but should not be used for cryptographic purposes. True random numbers are based on physical phenomena such as atmospheric noise, thermal noise, and other quantum phenomena.