Modular Arithmetic Calculator

Perform modular addition, multiplication, and exponentiation. Calculate (a op b) mod m with equivalence classes.

Modulus (m)

Operation

Tab to move between fields

Result

Expression(17 + 5) mod 13

Equivalence Class{..., -17, -4, 9, 22, 35, ...}

How to Use This Calculator

What each input means

Identify Input Parameters
4 parameters
a = 17, b = 5, Modulus (m) = 13, Operation = 1 = 4 input(s) provided
Calculate Result
9 = 9
Calculate Equivalence Class
Equivalence Class
{..., -17, -4, 9, 22, 35, ...} = {..., -17, -4, 9, 22, 35, ...}

Engine last updated August 5, 2026. Checked against 6 independently-derived tests — how we verify calculators.

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