Modulo Calculator
Calculate the modulo or remainder of any division, including negative numbers, with this free mod calculator that runs right in your browser.
Enter Values
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How to use this calculator
- Enter the number and the divisor.
- Press Calculate.
How it works
Modulo gives the remainder after dividing a by b.
Worked example
17 mod 5. = 2.
Common mistakes
- Confusing the remainder with the quotient — modulo gives what's left over, not how many times.
- Assuming a negative modulo behaves the same in every language; sign conventions differ.
Frequently asked questions
What does modulo do?
It gives the remainder of a division: 17 mod 5 = 2, because 17 = 3 × 5 + 2.
What is modulo used for?
Wrapping values (clock arithmetic), checking even/odd or divisibility, and cycling through indexes in programming.
Related tools
- GCD & LCM Calculator
- Nth Root Calculator
- Prime Number Checker
- Square Root Calculator
- Cube Root Calculator
- Engineering Prefix Calculator
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Cite this tool
Zerdly. (2026). Modulo Calculator. Retrieved from https://www.zerdly.com/tools/modulo-calculator/
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.