What is the absolute value of -4?

The absolute value of -4 is 4. This is because the absolute value of a number is its distance from zero on the number line, regardless of its sign. So, no matter if a number is positive or negative, the absolute value will always be positive. In this case, the absolute value of -4 is 4 because 4 units is the distance between -4 and 0 on the number line.