Math.min()

The static function Math.min() returns the lowest-valued number passed into it, or NaN if any parameter isn't a number and can't be converted into one.

Math.min()
Math.min(value0)
Math.min(value0, value1)
Math.min(value0, value1, ... , valueN)

value1, value2, ...

Zero or more numbers among which the lowest value will be selected and returned.

The smallest of the given numbers. If any one or more of the parameters cannot be converted into a number, NaN is returned. The result is Infinity if no parameters are provided.

Because min() is a static method of Math, you always use it as Math.min(), rather than as a method of a Math object you created (Math is not a constructor).

If no arguments are given, the result is Infinity.

If at least one of arguments cannot be converted to a number, the result is NaN.

This finds the min of x and y and assigns it to z:

var x = 10, y = -20;
var z = Math.min(x, y);

Math.min() is often used to clip a value so that it is always less than or equal to a boundary. For instance, this

var x = f(foo);

if (x > boundary) {
  x = boundary;
}

may be written as this

var x = Math.min(f(foo), boundary);

Math.max() can be used in a similar way to clip a value at the other end.

• Math.max()