What does this tool do?
The Modulo Calculator divides two numbers and shows the modulo, remainder, and quotient at the same time. It is handy for programmers, students, and anyone who wants to understand how negative numbers behave differently under modulo versus remainder.
How to use it
- Enter your values into the fields.
- The result is calculated instantly.
- Read or copy the result.
Modulo vs. remainder vs. quotient
This tool returns three results from one division. The remainder (%) mirrors the classic operator in most programming languages and can be negative when the dividend is negative. The modulo always returns a non-negative value, computed mathematically as ((a % b) + b) % b. The quotient is the result of integer (floor) division. Seeing all three side by side helps you understand why your language's % operator sometimes gives a sign you didn't expect.
Frequently asked questions
Why is -17 mod 5 equal to 3 but the remainder is -2?
The remainder copies the % operator in languages like JavaScript, which keeps the sign of the dividend, giving -2. The modulo always stays positive between 0 and the divisor, so it returns 3.
How is the quotient calculated?
The quotient is the floor of a / b. So 17 / 5 gives 3, and -17 / 5 gives -4 because flooring rounds toward negative infinity.
What happens if I divide by zero?
Division by zero is mathematically undefined, so the calculator skips the computation and shows a warning instead of a result.
Is Modulo Calculator free?
Yes. Modulo Calculator and all 300+ tools on MagmaNex are completely free with no signup or account required.
Is my data safe?
Yes. Everything runs locally in your browser. The data you enter is never sent to a server, stored, or shared.
Does it work on mobile?
Yes. Modulo Calculator works on phones, tablets and desktops — no app download needed.
🔒 Privacy: everything runs in your browser, your data is never sent to a server.