Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

GCD Calculator

Find the greatest common divisor — the largest integer that divides two whole numbers exactly with no remainder. Use it to simplify fractions, reduce ratios, and solve number-theory problems.

First Number

Second Number

Fill in the required fields to see your result.

Number Theory

Modular Arithmetic Calculator

Compute modular addition, subtraction, and multiplication instantly. Use it in cryptography, competitive programming, or number theory to keep results within a fixed range.

Number A

Number B

Modulus

Fill in the required fields to see your result.

Key differences

	GCD Calculator	Modular Arithmetic Calculator
Category	Number Theory	Number Theory
Inputs required	2	3
Result	Greatest Common Divisor	(A + B) mod M
What it does	Find the greatest common divisor — the largest integer that divides two whole numbers exactly with no remainder. Use it to simplify fractions, reduce ratios, and solve number-theory problems.	Compute modular addition, subtraction, and multiplication instantly. Use it in cryptography, competitive programming, or number theory to keep results within a fixed range.