JavaScript to Generate a Random Number Between X and Y

By Stephen Bucaro

You can use the JavaScript Math object's .random() method to generate a random number between two values, but because it returns a (pseudo) random floating-point number between 0 and 1 (but not including 1), you'll need to perform some additional operations on it to scale it to your required range.

To generate a random integer between two values x and y use the code shown below:

Math.floor((Math.random() * y) + x);

x being the lowest value, and y being the highest value.

For example if you wanted to generate a random integer between 1 and 8, you would use:

Math.floor((Math.random() * 8) + 1);

The Math.floor() function returns the largest integer less than or equal to the passed argument.

If the lowest random integer that you require is 0, you can simplify the statement as shown below:

Math.floor(Math.random() * max);

To generate a random floating-point number between two values x and y you would use the code shown below:

return Math.random() * (max-min) + min;

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