How Do You Trim a String in Javascript

In this tutorial, you will learn how do you trim a string in javascript. Trimming a string simply means removing any extra unwanted space at the beginning and at the end of the string. For a newbie developer, it can be a bit tricky to trim a string.

There are numerous ways to trim a string. But for the sake of simplicity, we will use trim() method. The trim() method removes any extra space at the beginning and at the end of a string.

In the following example, we have one global variable that holds a string. Upon click of a button, we will trim the string and display the result on the screen.  Please have a look over the code example and the steps given below.


  • We have 3 elements in the HTML file (div, button, and h1). The div element is just a wrapper for the rest of the elements.
  • The innerText for the button element is “Trim” 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">
  <link rel="stylesheet" href="style.css">


  <div class="container">    

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

.container {        
    text-align: center;

button {
  margin-top: 10px;
  padding: 10px 20px;


  • We have selected the button element and h1 element using the document.querySelector() method and stored them in btnTrim and output variables respectively.
  • We have a global variable myString which holds a text as its value.
  • We are displaying myString in the h1 element using innerText property.
  • We have attached a click event listener to the button element.
  • In the event handler function, we are calling trim() method to remove any extra space at the beginning as well as at the end of the string.
  • This trim() method will return a new string and we are storing that string in the result variable.
  • We are displaying the result in the h1 element using the innerText property.
let btnTrim = document.querySelector("button");
let output = document.querySelector("h1");

let myString = ` I just arrived   `;
output.innerText =  myString;
btnTrim.addEventListener("click", () => {  
  let result = myString.trim();
  output.innerText = result;