# How to Check if a Number is Positive or Negative in Javascript

In this tutorial, you will learn how to check if a number is positive or negative in javascript. The numbers below zero are negative numbers and similarly, the numbers above zero are positive numbers. For example, 1 is a positive number and -1 is a negative number.

A negative number is always prefixed with a minus (`-`) sign and a positive number is optionally prefixed with a plus (`+`) sign. Detecting whether a number is positive or negative is very easy, but it can be tricky if the number is coming from an input field because the value present in the input field is of string type. So first, we have to convert it into a number type using the `Number()` method and then perform the check.

In the following example, we have an input field in which we will enter a random number. Upon click of a button, we will check whether it’s negative or positive and display the result on the screen.  Please have a look over the code example and the steps given below.

HTML & CSS

• We have 4 elements in the HTML file (`div`, `input`, `button`, and `h1`). The `div` element is just a wrapper for the rest of the elements.
• The `innerText` for the `button` element is `“Check”` and for the `h1` element, it is `“Result”`.
• We have done some basic styling using CSS and added the link to our `style.css` stylesheet inside the `head` element.
• We have also included our javascript file `script.js` with a `script` tag at the bottom.
```<!DOCTYPE html>
<html lang="en">

<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>

<body>

<div class="container">
<input type="number" placeholder="Enter Number">
<button>Check</button>
<h1>Result</h1>
</div>

<script src="script.js"></script>
</body>

</html>```
```.container {
text-align: center;
}

button {
margin-top: 10px;
}

input {
display: block;
margin: 10px auto;
}

input[type=number]::-webkit-inner-spin-button,
input[type=number]::-webkit-outer-spin-button {
-webkit-appearance: none;
margin: 0;
}```

Javascript

• We have selected the `input` element, `button` element, and `h1` element using the `document.querySelector()` method and stored them in `input`, `btnCheck`, and `output` variables respectively.
• We have attached a `click` event listener to the `button` element.
• In the event handler function, we are passing the value of the `input` element to the `Number()` method and storing the number in the `num` variable.
• The `result` variable is `undefined` initially.
• We are using the `if` statement to verify whether the number is negative or positive. Depending upon the result of the check, we are setting the `result` variable equal to `“Positive”`, `”Negative”`, or `“Zero”`.
• We are displaying the `result` in the `h1` element using the `innerText` property.
```let input = document.querySelector("input");
let btnCheck = document.querySelector("button");
let output = document.querySelector("h1");