# Modulus % operator

I am so confused because I haven’t found any topic that explains what it does and how it works. Someone please explain me.

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basically the mod operator is used when you want to get the remainder of a division operation

for example:

``````
print(5%2) -- returns 1 cause 2*2+1 = 5
print(5%1) --  returns 0 cause 1*5+0 = 5``````

The % operator returns the remainder from division between 2 numbers.

For example, 3 % 2 would return 1, as 3 divided by 2 is 1.5, or 1 and has the remainder 1.
Other examples include:

• 10 % 2 returning 0, as there is no remainder;
• 5 % 6 returning 5, as 5 does not go into 6;
• 7 % 7 returning 0, as 7 goes into 7 perfectly.
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Modulus `a % b` goes hand in hand with floor division `a // b` (which currently isn’t natively supported by Luau, but you can use `math.floor(a / b)` instead)

Floor division gives you how many times something fits into something, and modulus tells you what is left out

To add on to using the `math.floor()` function, which was mentioned by @Prototrode as well, this is the exact formula to get the remainder of a division operation:

``````local formula = a - (b * (math.floor(a / b)))
``````

which is equivalent to

``````local formula = a % b
``````

still dont understand bc im bad in math

aka the remainder is the result of the % operator

``````print(10%2) -- returns: 2?
``````

oh wait I has understand it. actually I learned it in school, ive just got confused lol

``````print(10%2) -- returns: 2?
``````

No, it returns 0 since 10 divided by 2 equals 5, has no remainder.

That would be 0.

Another way is so think of it like this:
Say we have the following:

``````local Number = 7 % 3
Number = ?
``````

Our number will be the remainder of the division of (7/3), or in other words, keep subtracting from 3 from 7 until we can’t anymore without going negative.

In this case we can subtract twice.
7 - 3 = 4
4 - 3 = 1
Thus, 7 % 3 = 1.

And in this case:

``````local Number = 12 % 6
``````

12 - 6 = 6
6 - 6 = 0
Therefore, 12 % 6 = 0

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