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.