Question

Does anyone know how to round up a number to its nearest multiple of 5? I found an algorithm to round it to the nearest multiple of 10 but I can’t find this one.

This does it for ten.

double number = Math.round((len + 5)/ 10.0) * 10.0;

Answer 1

int roundUp(int n) {
    return (n + 4) / 5 * 5;
}

Note – YankeeWhiskey’s answer is rounding to the closest multiple, this is rounding up. Needs a modification if you need it to work for negative numbers. Note that integer division followed by integer multiplication of the same number is the way to round down.