Looking for calculating **JavaScript square root**? In this quick tutorial, you will learn how to find the **square root of a number** in JavaScript.

In, the previous JavaScript tutorial we used the inbuilt method pow() in Math class to find the **square of a number**.

## Using Math.sqrt() Method to Find Square Root

The **Math.sqrt()** method accepts a single argument of type number.

**Syntax:**

`Math.sqrt(x);`

Where **x** is a positive number for which you want to find the square root.

## JavaScript Program to Find the Square Root

For example, here are a few JS programs to find the square root.

**Example 1**: JavaScript square root of a positive number.

```
let val = 49;
console.log(Math.sqrt(val)); // 7
```

**Example 2**: JavaScript square root of a floating-point number?

```
let val = 5.14;
console.log(Math.sqrt(val)); // 2.226...
```

**Example 3**: What if we pass a negative number to sqrt() method?

```
let val = -9;
console.log(Math.sqrt(val)); // NaN
```

As a result, If a negative number is passed NaN is returned.

**Example 4**: What if a number is passed as a string to Math.sqrt() method?

```
let val = '36';
console.log(Math.sqrt(val)); // 6
```

Isn’t it strange? We passed a number as a string, then also the sqrt() method returns its square root. Check for yourself.

**Example 5**: What if a word is passed as a string?

```
let val = 'two';
console.log(Math.sqrt(val)); // NaN
```

Similarly, if a string containing alphabets is passed then **NaN** is returned.

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