Generate .exe Installer for Your Flutter Windows App Using Inno Setup — Step-by-Step Guide

Flutter lets you build beautiful desktop apps, and with flutter build windows, you can get a fully functional Windows application. But when it comes to distributing your app, you don’t want to share a folder full of DLLs — you want a clean .exe installer just like professional software.

Enter Inno Setup — a free, lightweight, and powerful tool for creating Windows installers.

In this story, I’ll guide you through packaging your Flutter desktop app into a .exe installer using Inno Setup, so users can install your app with a double-click.

🔧 Prerequisites

Before we start, make sure you have:

• ✅ A working Flutter Windows app
• ✅ Inno Setup installed
• ✅ Your app built in release mode

🏗 Step 1: Build the Flutter App for Windows

Open your terminal and run:

flutter build windows

This command will generate a release version of your app in:

build/windows/runner/Release/

This folder contains:

• Your app .exe file
• Dependencies (.dll, assets, fonts, etc.)

📁 Step 2: Create an Installer Folder

Organize your app files before packaging:

Create a new folder, e.g. installer_files/

Copy everything from build/windows/runner/Release/ into installer_files/

Make sure it contains:

• YourApp.exe
• All necessary .dll files
• data folder
• Assets

You can even add a license file or README.

📝 Step 3: Write an Inno Setup Script (.iss)

Now create a script file installer_script.iss with the following content:

[Setup]
AppName=YourAppName
AppVersion=1.0.0
DefaultDirName={pf}\YourAppName
DefaultGroupName=YourAppName
OutputDir=output
OutputBaseFilename=YourAppInstaller
Compression=lzma
SolidCompression=yes

[Files]
Source: "installer_files\*"; DestDir: "{app}"; Flags: recursesubdirs

[Icons]
Name: "{group}\YourAppName"; Filename: "{app}\YourApp.exe"
Name: "{group}\Uninstall YourAppName"; Filename: "{uninstallexe}"

🔎 Modify AppName, OutputDir, and Source as needed. Make sure paths are correct.

🛠 Step 4: Compile the Installer

1. Open the Inno Setup Compiler (comes with the installation)
2. Load your .iss script
3. Click Compile

Once done, you’ll find the .exe installer inside the output/ directory (or your specified folder).

🚀 Step 5: Test the Installer

Double-click the .exe file and walk through the installation wizard:

• It installs the app in Program Files\YourAppName
• Adds a Start Menu shortcut
• Provides an uninstall option

🔐 Bonus: Code Signing Your Installer (Optional)

To increase trust and avoid Windows SmartScreen warnings, sign your .exe file with a code signing certificate:

signtool sign /a /tr http://timestamp.digicert.com /td sha256 /fd sha256 YourAppInstaller.exe

This step is optional, but recommended for production apps.

✅ Summary

With Inno Setup, you’ve gone from:

👉 A release folder full of files ➡️ To a sleek .exe installer ready for distribution

No more zip files or manual instructions — just a professional installation experience for your users.

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