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# How to Round Floating-Point Numbers in JavaScript?

Oftentimes, we’ve to round floating-point numbers in our JavaScript web apps.

In this article, we’ll look at how to round floating-point numbers in JavaScript.

### Number.prototype.toFixed

JavaScript numbers have the `toFixed` method that returns a string version of the number rounded to the number of decimal places we passed in as the argument.

For instance, we can write:

``````const rounded = Number((6.6756854).toFixed(1));
console.log(rounded)
``````

Then `rounded` is `'6.7'` since we passed in 1 to `toFixed` .

This makes it returns a string rounded to 1 decimal place.

### Math.round

Another way to round floating-point numbers is to use the `Math.round` method.

`Math.round` returns the rounded number instead of a string.

So we can use it if we want to round a number and keep the returned result as a number.

For instance, we can write:

``````const number = 6.6756854
const rounded = Math.round(number * 10) / 10;
console.log(rounded)
``````

If we want to round to 1 decimal place, then we multiply the `number` by 10.

Then we call `Math.round` on that number.

Then we divide by 10 to get the rounded number.

So `rounded` is `'6.7'` .

If we want to round to 2 decimal places, then we replace 10 with 100.

And if we round to 3 decimal places, we replace 10 with 1000, and so on.

### Number.prototype.toPrecision

We can also use the number’s `toPrecision` method to return a number that’s rounded to the given decimal place.

It also returns a number instead of a string.

For instance, we can write:

``````const rounded = (6.6756854).toPrecision(2)
console.log(rounded)
``````

The argument is the number of decimal places to round to.

So passing in 2 as the first argument would round the number we call it into 2 decimal places.

Therefore, `rounded` is 6.7.

### Math.floor

We can use the `Math.floor` method to round a number down to the nearest integer.

For instance, we can write:

``````const rounded = Math.floor(6.6756854)
console.log(rounded)
``````

Then `rounded` is 6.

### Math.ceil

The `Math.ceil` method lets us round a number up to the nearest integer.

For instance, we can write:

``````const rounded = Math.ceil(6.6756854)
console.log(rounded)
``````

And `rounded` is 7.

### Conclusion

There’re various `Math` static methods and number instance methods that we can use to round floating-point numbers the way we like. ## By John Au-Yeung

Web developer specializing in React, Vue, and front end development.