a mod b is the remainder when a is divided by b. For example, 17 mod 5 = 2.

What if b is negative?

We use the sign of the divisor b; result is in the range [0, |b|) or (|b|, 0] depending on b.

Online Modulo Calculator

Compute a mod b: the remainder when a is divided by b. Handles negative numbers with standard remainder behavior.

a (dividend)

b (divisor)

What is modulo?: a mod b is the remainder when a is divided by b. For example, 17 mod 5 = 2.
What if b is negative?: We use the sign of the divisor b; result is in the range [0, |b|) or (|b|, 0] depending on b.

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