Remainder Calculator

Divide dividend by divisor to find modulo/remainder
Solution
Steps
a b = r
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About this tool

The Modulo operation, often abbreviated as "mod," finds the remainder when one number is divided by another. It is expressed as $$a \bmod b$$, where $$a$$ is the dividend and $$b$$ is the divisor.

What is the Modulo Operation?

The modulo operation calculates the remainder when a number is divided by another. For example, in $$17 \bmod 5$$, dividing 17 by 5 gives a quotient of 3 and a remainder of 2. Hence, $$17 \bmod 5 = 2$$.

In mathematical terms, $$a \bmod b = r$$, where:

  • $$a$$ is the dividend.
  • $$b$$ is the divisor.
  • $$r$$ is the remainder such that $$0 \leq r < b$$.

How Does the Modulo Work?

Modulo can be understood in terms of repeated subtraction. It subtracts the divisor from the dividend until the remainder is less than the divisor. For example:

  • $$23 \bmod 7$$: Subtract 7 repeatedly from 23: $$23 - 7 - 7 - 7 = 2$$. Thus, $$23 \bmod 7 = 2$$.
  • $$10 \bmod 3$$: Subtract 3 repeatedly from 10: $$10 - 3 - 3 - 3 = 1$$. So, $$10 \bmod 3 = 1$$.

Applications of Modulo

  • Computer Science: Modulo is widely used in programming, such as determining even or odd numbers ($$n \bmod 2 = 0$$ for even numbers).
  • Cryptography: Modulo plays a key role in algorithms like RSA for secure data encryption.
  • Calendars: Calculating days of the week often uses modulo. For example, finding the day after 100 days can be done with $$100 \bmod 7$$.
  • Clock Arithmetic: Modulo is used in 12-hour and 24-hour time calculations. For example, $$15 \bmod 12 = 3$$ represents 3 PM.

Properties of Modulo

  • Non-Negative Result: The modulo operation ensures the remainder is always non-negative, even if the dividend is negative.
  • Distributive Property: Modulo is distributive over addition and subtraction: $$\left(a + b\right) \bmod c = \left[\left(a \bmod c\right) + \left(b \bmod c\right)\right] \bmod c$$.
  • Multiplication: $$\left(a \cdot b\right) \bmod c = \left[\left(a \bmod c\right) \cdot \left(b \bmod c\right)\right] \bmod c$$.

Using Our Modulo Calculator

Our modulo calculator is a simple tool to compute the modulo of any two numbers. Simply enter the dividend and divisor, and it will instantly calculate the remainder for you.

Whether you're solving math problems, coding algorithms, or working with modular arithmetic, this tool makes calculations effortless!

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