How to Change Thumbnail Image in Dropzone JS?

By Hardik Savani November 5, 2023 Category : jQuery

This article will give you example of dropzone replace thumbnail image. This tutorial will give you simple example of dropzone thumbnail image change example. you will learn dropzone set thumbnail image for non image. you'll learn dropzone set default thumbnail.

Sometime we need to add default image for non image type in dropzone js. when you have file upload allow for all like images, pdf, zip etc then you have to set default thumbnail image for pdf, zip and csv file. so here i will show you how to set default image on dropzone js.

Dropzone provide success function and we will check if uploaded file is not image then we will set default thumbnail using createThumbnailFromUrl. so let's see bellow example.


Step 1: Create index.php file

In first step we have to create index.php file in our root folder and copy bellow code and put on that file. In this file i use cdn for bootstrap, jquery, dropzone css and js.

we will write click event for button and when you click on that button then and then images will upload to server.

So let's follow:


<!DOCTYPE html>



<title>How to Change Thumbnail Image in Dropzone JS</title>

<link href="" rel="stylesheet">

<script src=""></script>



<div class="container">

<div class="row">

<div class="col-md-12">

<h2>How to Change Thumbnail Image in Dropzone JS -</h2>

<form action="upload.php" enctype="multipart/form-data" class="dropzone" id="image-upload">

<input type="hidden" name="request" value="add">


<h3>Upload Multiple Image By Click On Box</h3>






<script type="text/javascript">

Dropzone.autoDiscover = false;

var myDropzone = new Dropzone(".dropzone", {

maxFilesize: 10,

success: function (file, response) {

var ext = getFileExt(;

var newImagePath =;

/* Check for extension */

if(ext != 'png' && ext != 'jpg' && ext != 'jpeg' && ext != 'gif'){

newImagePath = "upload/default-image.jpg";


this.createThumbnailFromUrl(file, newImagePath);



function getFileExt(fileName){

fileName = fileName.toLowerCase();

return fileName.split('.').pop();





Step 2: Create upload.php file

In first step we have to create upload.php file in our root folder. In this file i write image upload folder code.



$uploadDir = 'upload';

$tmpFile = $_FILES['file']['tmp_name'];

$filename = $uploadDir.'/'.$_FILES['file']['name'];


echo $filename;


Step 3: Create upload folder

In last step, we have to just create "upload" folder for store images. You can also give different name from uploads, But make sure also change on upload.php file.

Ok, now we are ready to run this example, so just run bellow command on root folder for run your project.

php -S localhost:8000

Now you can open bellow url on your browser:


I hope it can help you...