# Round a Number Up to the Nearest 100 in JavaScript Wed Oct 27 20211 min read Photo by Jason Strull

## Round a Number Up to the Nearest 100#

To round a number up to the nearest 100, call the `Math.ceil` function, passing it the number divided by `100` as a parameter and then multiply the result by `100`, e.g. `Math.ceil(num / 100) * 100`. The `Math.ceil` function rounds a number up to the next largest integer.

index.js
```Copied!```function roundUpToNearest100(num) {
return Math.ceil(num / 100) * 100;
}

console.log(roundUpToNearest100(101)); // 👉️ 200
console.log(roundUpToNearest100(199)); // 👉️ 200
console.log(roundUpToNearest100(100.001)); // 👉️ 200
console.log(roundUpToNearest100(-399)); // 👉️ -300
console.log(roundUpToNearest100(-301)); // 👉️ -300
``````

If you need to round up or down to the nearest 100, check out my other article - Round a Number (up or down) to the Nearest 100.

If the number we passed to the Math.ceil function has anything after the decimal, the number gets rounded up.

If an integer is passed to the `Math.ceil` function, it simply returns the number as is.

Here are some examples of using the `Math.ceil` function.

index.js
```Copied!```console.log(Math.ceil(10.01)); // 👉️ 11
console.log(Math.ceil(19.01)); // 👉️ 20
console.log(Math.ceil(20)); // 👉️ 20
console.log(Math.ceil(-10.99)); // 👉️ -10

console.log(Math.ceil(null)); // 👉️ 0
``````
If you pass a `null` value to the `Math.ceil` function, it returns `0`.

Here are the steps we took to get to the solution.

index.js
```Copied!```console.log(601 / 100); // 👉️ 6.01
console.log(900 / 100); // 👉️ 9

console.log(Math.ceil(601 / 100)); // 👉️ 7
console.log(Math.ceil(900 / 100)); // 👉️ 9

console.log(Math.ceil(601 / 100) * 100); // 👉️ 700
console.log(Math.ceil(900 / 100) * 100); // 👉️ 900
``````

The process consists of 2 steps:

1. Divide the number by `100` and round the result up to the next largest integer.
2. Multiply the result by `100` to get the number rounded up to the nearest `100`. 