What is the modulo operation?

It returns what's left over after dividing one number by another. 17 mod 5 = 2 because 17 = 3×5 + 2.

Why are there two remainder results?

Languages differ on negative numbers. The truncated remainder (JS/C) takes the dividend's sign; the floored modulo (Python) takes the divisor's sign. For positive inputs they're identical.

Modulo Calculator

Free modulo calculator. Enter a dividend and divisor to get the remainder (truncated, like a % b in most languages), the floored modulo (sign follows the divisor), and both the truncated and floored quotients.

Find the remainder and quotient of a division, two ways.

a mod b = a - b ⌊ a / b ⌋

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