Random Number Generator
Generate random numbers in any range, flip a coin, roll dice, or pick randomly from a list.
Frequently Asked Questions
How does a random number generator work?
This tool uses JavaScript's Math.random() function, which generates a pseudorandom floating-point number between 0 and 1. For integers, the result is scaled to your chosen range and floored. For unique results, previously generated numbers are tracked and excluded from subsequent draws. The randomness is sufficient for games, simulations, and everyday decisions.
Are these numbers truly random?
They are pseudorandom, which means generated by a deterministic algorithm seeded with a hard-to-predict value (like the current time). For most everyday purposes — picking a winner, rolling virtual dice, choosing a number for a game — pseudorandom numbers are perfectly adequate. True randomness from physical processes is only necessary in high-stakes cryptographic applications.
What is the difference between random integers and decimals?
A random integer is a whole number with no decimal part, such as 7, 42, or 99. A random decimal includes a fractional component, such as 7.348 or 42.91. Integers are used for dice rolls, lottery picks, and list selections. Decimals are useful for simulations, probability experiments, and cases where you need more granularity than whole numbers provide.