# Generate Random Number in a specific range in JavaScript

Here we will learn how to generate random number in a specific range in JavaScript.

In JavaScript, we can generate random numbers using it’s in-built `Math.random()`

method.

The `Math.random()`

function returns floating-points number between 0 and 1 (inclusive of 0 and exclusive of 1). with uniform distribution over that range.

Since `Math.random()`

returns the number in decimal between 0 and 1. So , we have to multiple it with an integer to set range higher then 1.

**Example:**

```
// Returns a random integer from 0 to 4 (exclusive of 5)
Math.random() * 5
//output : 4.9878652
```

You can also see that the max value (here 5) is always excluded in `Math.random()`

results number.

To include the max value in the range we have to add **+1** at the end of it.

**Example:**

```
//To get the random between 1 to 100 (inclusive of 100)
Math.random() * 100 + 1;
//output : 67.9878652
```

Since the results are in decimal, you can round it up to an integer using `Math.floor()`

method in JavaScript.

**Example:**

```
Math.floor(Math.random() * 100 )+ 1;
//output: 67
```

## What if the min value is not 0?

To solve that issue, we get the difference between the **min** and **max** value and multiple with the the randomly generated number. It will return us an integers.

For example, if we have a range between 1 to 5 then the delta value will be 5-1 i.e 4 so the random number generated will be between 0 and 3.9999.

And now we just have to add the min value to it and it will shift into the right range.

So using `Math.random()`

and `Math.floor()`

we can generate random integers between a specific range.

## [Complete code]Generate random numbers in JavaScript within a range.

So here we will code a function which will take two numbers min value and max value(exclusive) and will return use a randomly generated integer.

**Exclusive of max value:**

```
function randomNum(min, max) {
return Math.floor(Math.random() * (max - min) ) + min;
}
console.log(randomNum(1,4))
//output: 1 or 2 or 3
```

**Inclusive of the max value:**

We just have to add **+1** to the difference of max and min value.

```
function randomNum(min, max) {
return Math.floor(Math.random() * (max - min + 1) ) + min;
}
console.log(randomNum(1,4))
//output: 1 or 2 or 3 or 4
```

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