Make a Windows installer for a Python app (PyInstaller to Setup.exe)

PyInstaller turns a Python program into a Windows .exe that runs without Python installed. What it doesn't do is install that program: no Start Menu entry, no uninstaller, nothing in Windows Settings. For that you wrap PyInstaller's output in an installer. Here is the whole path, from script to Setup.exe.

Step 1: freeze the app with PyInstaller

Install PyInstaller in the project's environment, then build from the folder that holds your entry script:

pip install pyinstaller
pyinstaller --noconsole --onedir --name MyApp --icon app.ico main.py

What the flags do:

• --onedir (the default) produces a folder dist/MyApp/ with MyApp.exe and an _internal/ folder of libraries. Use this for installers. It starts faster than --onefile, because nothing has to be unpacked to a temp folder at every launch, and it draws less attention from antivirus heuristics.
• --noconsole hides the black console window for GUI apps (Tkinter, PyQt, Kivy and so on). Leave it out for command-line tools.
• --icon app.ico embeds the icon in the .exe. Keep the same .ico for the installer.
• --name MyApp names the executable and the output folder.

Data files your program opens at run time (images, config templates, models) must be added with --add-data "src;dest" or in the .spec file, or they won't be in dist/MyApp/.

Open dist/MyApp/MyApp.exe and check the app runs. Copy the whole dist/MyApp folder to another Windows PC without Python if you can, and run it there too.

Step 2: zip the output folder

Zip the contents of dist/MyApp/: MyApp.exe and _internal/. Don't include build/, the .spec file or your source tree. The zip is what gets installed, byte for byte.

Step 3: build the installer

1. Upload the zip to ExeTup. It finds MyApp.exe as the main program.
2. Enter the app name, version, publisher and an optional licence.
3. Choose all users (Program Files, admin prompt) or current user (no admin rights needed). Tools distributed to colleagues often work best per user.
4. Choose the architecture. PyInstaller builds for the Python you ran it with, so a 64-bit Python gives a 64-bit app.
5. Upload app.ico, turn on the shortcuts you want, and build.
6. Download Setup.exe and test it on Windows.

Python-specific notes

• Antivirus false positives. PyInstaller bundles are a frequent target of overcautious antivirus heuristics, especially --onefile builds. A onedir build inside a normal installer, placed in Program Files, behaves like any other program and is less likely to be flagged. Code signing helps further.
• Size. A Tkinter app is 20 to 40 MB; PyQt, NumPy or PyTorch push that far higher. The installer's LZMA compression typically halves it. Exclude modules you don't use with --exclude-module to keep it lean.
• First launch. Because onedir needs no unpacking, the first start is as fast as later ones.
• Updates. Ship a new installer with a higher version number. Installing over the previous version replaces the files in place.
• Console tools. For a command-line program, consider a per-machine install and tell users the install folder; the installer does not add it to PATH.

Alternatives

Nuitka and cx_Freeze also produce a folder with an .exe; the installer step is identical. If you want to write the installer script yourself, NSIS and Inno Setup both work with PyInstaller output.

FAQ

Should I use --onefile or --onedir for an installer?

--onedir. The installer already gives users a single Setup.exe to download, so there is no reason to pay onefile's slow start-up and temp-folder unpacking. Onedir is also the PyInstaller default.

Do users need Python installed?

No. PyInstaller bundles the Python interpreter and the libraries into the folder, and the installer puts that folder on the user's machine.

Why does Windows warn about my installer?

New, unsigned downloads trigger Microsoft SmartScreen until they gain a reputation. See the SmartScreen guide for what you can do.

Can I include a sample config or data folder?

Yes. Either add it with PyInstaller's --add-data, so it lands inside _internal/, or add it in ExeTup's "Other files" step to place it next to MyApp.exe.