The Remainder Operator in JavaScript | Modulo %

The Remainder Operator (%) in JavaScript allows you to find the remainder of a division of two numbers - much similar to the modulo operator in many other languages. It can be used for the same purpose of finding the remainder as it uses the built in modulo function.

It is also extremely useful for limiting a large number (or converting it) into a smaller one with a maximum you specify. For example if you wanted to reduce 500 down to a maximum of 7, you can do this easily using the remainder operator.

In this video I take you through a basic example of the operator as well as it's uses to limit a number down.

For your reference, check this out:

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[AndHunt]

This is the first video I've seen that introduces the concept of reducing a large number to a smaller one. I've only seen modulo being used to determine odd or even numbers. Thank you!

[starterdev]

You're the best

Whenever there's something I need to know in JS, you're always the first person that comes on my mind...

Thanks for the great tutorials

[ProgrammingNote.-bznq]

Thanks! the remainder operator (%) is very useful. And you explain it very well.

[luciusrex]

Came across the code below and your explanation @1:18 was all I needed to understand what was happening:

```javascript
var labels = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
var labelIndex = 0;

label = labels[labelIndex++ % labels.length];
```

Nice work!

[patfoiloofficial]

Nice tutorial but too advanced for beginners. I think you should have two videos on this.

[RainOnline]

keep on making videos, you're awesome!

[vonline]

Nice and informative video. Thank you.

[bboyjojo]

Red john sound like a fiction serial killer. Nice lesson bro

[darith]

How do you explain these remainders?

A) 1 % 2 // 1

B) 2 % 3 // 2

[joelnyberg]

Hey there! I'm running into an issue with Visual Studio Code.
I cant run the console log for some reason with the terminal.
It says that node isnt recognized, and when i manually enter the path to the index save, it gives me a syntax error.. any clue why?

[victorartb]

I couldnt understand the logic behind! still lost 😵

[DeathBeach]

just watched a video for idiots and cant understand this concept. would be lovely to see this done in long form math to really understand the magic that is happening here. saying to divide something and you do it on a calculator and it doesnt come out the same as this. no amount of math does. so are we not doing math in the traditional sense?

[encapsule]

o fuck i thought it was just division this whole time and couldnt figure out why it was acting weird lool

[Phill]

i understand how % works but i don't get how you got a color based on a name. please someone explain

[dilluminatilair]

that sure is one loud keyboard. sheesh

[XFunkWizardX]

Hi, math idiot here. Can anyone explain why dividing 5 by 2 gives the answer of 2.5 but instead of the % operator returning 5 it returns 1?