JavaScript Random Numbers (Random)

Math.random()Method returns 0-1a range of floating-point random numbers (including 0, but not including1).

Math.random();

Note: Math.random()Always returns a floating-point random number between 0 and1between floating-point numbers.

JavaScript Random Integer

Math.random()with Math.floor()can be used together to return random integers.

This example returns a random integer from 0 to9to

Math.floor(Math.random()　*　10);

This example returns a random integer from 0 to10to

Math.floor(Math.random()　*　11);

This example returns a random integer from1to10to

Math.floor((Math.random()　*　10)　+　1);

This example returns a random integer from1to100's random integer:

Math.floor((Math.random()　*　100)　+　1);

This example returns a random integer from11to20's random integer:

Math.floor((Math.random()　*　10)　+　11);

This example returns a random integer from51to100's random integer:

Math.floor((Math.random()　*　50)　+　51);

Get a random number between two values

This example returns a random number between min (inclusive) and max (exclusive):

function getRandom(min, max) {
　　　return Math.floor(Math.random()　*　(max　-　min))　+　min;
}

This example returns a random number between min and max (both inclusive):

function getRandom(min, max) {
　　　return Math.floor(Math.random()　*　(max　-　min　+　1))　+　min;
}

More Examples

Return the random number of mouse movement: