About this Modulo Calculator
Modulo Calculator finds the remainder that remains after dividing one real integer-style value by another non-zero value.
Formula or method
Remainder r satisfies a = bq + r with 0 ≤ r < |b|.
Example
17 mod 5 = 2.
Common uses
- Check cyclic arithmetic.
- Find remainders in programming exercises.
- Test divisibility patterns.
How to use this tool
- Enter the values or text requested by the calculator.
- Choose units or options when the tool provides them.
- Select the calculation button and review the result.
- Use the formula, example and notes on this page to check whether the result fits your situation.
Important note
The divisor cannot be zero. This tool normalizes the result to a non-negative Euclidean remainder.
Frequently asked questions
What happens with a negative dividend?
The tool normalizes the remainder to a non-negative value smaller than the absolute divisor.
Can the divisor be zero?
No. Division and modulo by zero are undefined.