File upload through flutter web and Nodejs, multer….

Arpit Sharma
2 min readMay 13, 2021

As everyone knows flutter web file path comes null when a file is being selected.
file.path = null

To upload the file first lets create multer supported Nodejs backend to save file inside system.

Packages used


Multer is a node.js middleware for handling multipart/form-data, which is primarily used for uploading files. It is written on top of busboy for maximum efficiency


Decode base64 to image and save the image to disk.

Flutter File Picker

A package that allows you to use the native file explorer to pick single or multiple files, with extensions filtering support.

Flutter Http

This package contains a set of high-level functions and classes that make it easy to consume HTTP resources. It’s multi-platform, and supports mobile, desktop, and the browser.

Flutter code to pick and make API call

Backend Nodejs code for accepting file

Json format req should send{       "filename":"arpit",
}*base64 url is to big to display

I hope this helps you……
Github Repository :



Arpit Sharma

R&D Engineer 2 Broadcom (VMware) | SIH'20 Winner #1 | Former Research Intern at Mitacs ( École de technologie supérieure )