NodeJS File Uploading

In this tutorial, we'll dive into file uploading in Node.js. We'll cover both single file uploading and multi-file uploading scenarios. So, let's get started and learn how to handle file uploads in Node.js!

Setting Up the Project

Before we jump into file uploading, let's set up a new Node.js project. Follow these steps to get started:

Step 1:

Create a new directory for your project and navigate to it in your terminal.

Step 2:

Initialize a new Node.js project by running the following command:

This will generate a package.json file for your project.

Step 3:

Install the necessary modules by running the following command:

We'll be using the express framework for our server and the multer middleware for handling file uploads.

Handling Single File Uploads

Let's start with handling single file uploads. We'll set up an Express.js server that accepts a single file upload and saves it to a specified destination.

Step 1:

Create a new JavaScript file, e.g., server.js, and require the necessary modules at the top of the file:

Step 2:

Set up a route that handles the file upload:

In this example, we've set up a POST route at /upload that uses the upload.single() middleware to handle a single file upload. The upload.single() method specifies that the field name of the file input is 'file'. The uploaded file can then be accessed using req.file, and you can process it as needed.

Step 3:

Start the server and listen for incoming requests:

That's it! You now have a server that can handle single file uploads. Run the command node server.js in your terminal, and your server will be up and running.

Handling Multi-File Uploads

Now, let's extend our file uploading functionality to handle multiple file uploads. We'll modify our Express.js server to accept and process multiple files.

Step 1:

Modify the route to use upload.array() instead of upload.single():

In this example, we've modified the route to use upload.array() instead of upload.single(). The upload.array() method specifies that the field name of the file input is 'files', indicating that multiple files can be uploaded. The uploaded files can be accessed using req.files, which is an array of file objects.

Step 2:

Update the form to include the multiple attribute:

To enable multi-file uploads in the HTML form, we've added the multiple attribute to the file input field.

Step 3:

Restart your server and test the multi-file upload functionality by selecting and uploading multiple files.

That’s it! You've successfully learned how to handle file uploading in Node.js, both for single file uploads and multi-file uploads. You now have the knowledge to accept file uploads, access the uploaded files, and process them as needed.

Remember, file uploading involves security considerations. Make sure to validate and sanitize user input, set appropriate file size limits, and implement proper error handling to ensure the security and reliability of your application.

Feel free to explore additional features provided by the multer middleware, such as setting destination paths, defining file name patterns, and limiting file types.


Yes, validating uploaded files is essential to prevent malicious files or unexpected data from being uploaded to your server. Always validate the file types, sizes, and perform security checks to ensure the safety of your application.

Yes, you can integrate file uploading with your web application's frontend using HTML forms with the enctype attribute set to multipart/form-data. You can also use frontend frameworks and libraries like React or Vue.js to handle file uploads.

To improve file uploading performance, consider implementing client-side validation, compressing files before uploading, and optimizing server-side code. You can also use CDNs (Content Delivery Networks) to store and serve uploaded files.