For most people, PyInstaller is the best Python-to-EXE converter — it's the most popular, works on Windows/macOS/Linux, and bundles everything into one file. auto-py-to-exe is just a friendly GUI on top of it. If you want py-to-exe without PyInstaller, use Nuitka (compiles your Python to C, so it's faster and the hardest to reverse) or cx_Freeze (simple, cross-platform). py2exe is Windows-only and largely legacy. One caveat none of them advertise: bundling to an .exe does not protect your source — obfuscate first (more below).
Turning a Python script into a standalone .exe so users can run it without installing Python is one of the most common packaging tasks — and there are five tools people reach for. They're not equivalent: they differ in how they build, what they output, whether they protect your code, and how painful the setup is.
I built a real one-file exe with the most popular tool (PyInstaller) for a concrete baseline, then compared the alternatives on the attributes that actually decide which one you should use.
The five Python-to-EXE tools, compared
| Tool | How it works | Output | Reverse-engineering barrier | Best for |
|---|---|---|---|---|
| PyInstaller | Bundles your .pyc + a Python interpreter | One file or a folder | Low (bytecode extracts + decompiles) | Most people — default choice |
| auto-py-to-exe | GUI wrapper around PyInstaller | Same as PyInstaller | Low (it *is* PyInstaller) | Beginners who want a UI |
| Nuitka | Compiles Python → C → native binary | Real machine-code exe | Higher (no bytecode to extract) | Speed + the strongest protection |
| cx_Freeze | Freezes into an exe + dependency folder | Folder with exe | Low (bytecode) | Simple cross-platform freezing |
| py2exe | Freezes to Windows exe (older) | Windows exe | Low (bytecode) | Legacy Windows-only projects |
The quick read: PyInstaller (and its GUI, auto-py-to-exe) is the default because it's the most popular, best-documented, and cross-platform. Nuitka is the standout when you care about speed or protection, because it genuinely *compiles* rather than bundles. cx_Freeze and py2exe are simpler/older alternatives.
The PyInstaller baseline (a real build)
PyInstaller is the one to start with, so here's a concrete build. I packaged a small script into a one-file exe:
# input: invoice_tool.py (921 bytes, Python 3.11.5)# output: dist/invoice_tool.exe -> 8,346,433 bytes (~8 MB)# built with PyInstaller 5.9.0
That ~8 MB is mostly the bundled CPython runtime — even a tiny script produces a multi-megabyte exe because the whole interpreter ships inside it. That's normal and true of every tool here except when you strip/optimize. PyInstaller's strengths: one command, cross-platform, huge community, handles most dependencies automatically. auto-py-to-exe produces the exact same output through a point-and-click UI, so pick it if you prefer not to touch the command line.
Py-to-EXE without PyInstaller: Nuitka & cx_Freeze
If you specifically want an alternative to PyInstaller, there are two real ones:
- Nuitka — the most interesting alternative. It doesn't bundle bytecode; it translates your Python into C and compiles it to a native binary. That usually means faster startup/runtime and, crucially, a much higher reverse-engineering barrier — there's no
.pycto extract and decompile, just machine code. The trade-offs: it needs a C compiler, builds are slower, and output is per-platform. - cx_Freeze — a simpler freezer that, like PyInstaller, bundles your bytecode plus the interpreter, typically into a folder with the exe. It's lightweight and cross-platform but offers no more protection than PyInstaller.
For the full head-to-head on the two that matter most for protection and performance, see PyInstaller vs Nuitka.
The catch: an .exe does NOT protect your code
This is the thing every "py to exe" tutorial skips. Bundling your script into an .exe makes it *distributable*, not *private*. With PyInstaller, cx_Freeze, py2exe (and auto-py-to-exe), the exe just contains your `.pyc` bytecode — and that extracts and decompiles back to near-original source. I showed this end-to-end in decompiling a PyInstaller exe: a tool called pyinstxtractor pulls the .pyc out, and the hard-coded secrets read in plain text. See also does PyInstaller protect Python source code?.
- Obfuscate the source before you build. Rename identifiers and encrypt strings with our free Python Obfuscator first, then run PyInstaller on the result — so the extracted bytecode is unreadable.
- Or compile with Nuitka, which ships machine code instead of bytecode — the highest built-in barrier of these tools.
- Keep real secrets off the client either way — a hard-coded key survives in the bytecode verbatim (protect API keys in Python).
Which converter should you use?
- Just ship a working exe, cross-platform, minimum fuss → PyInstaller (or auto-py-to-exe for a GUI).
- Faster binary + the strongest built-in protection → Nuitka (accept the C compiler + slower builds).
- Simple freezing without PyInstaller → cx_Freeze.
- An old Windows-only project already using it → py2exe, otherwise skip it.
- You mainly care about protecting the code → obfuscate first, then PyInstaller — or use Nuitka. Bundling alone isn't protection.
Prefer not to install a toolchain at all? Our Python to EXE page and how to convert Python to EXE online cover the no-install route, and the full PyInstaller walk-through has the step-by-step build.
Protect your Python before you package it — free
An .exe only bundles bytecode that decompiles back to source. Run your code through our free AST Python Obfuscator first, then build — so the extracted bytecode is unreadable.
Open the Python ObfuscatorFree tools mentioned here
Related guides
Frequently asked questions
What is the best Python to EXE converter?
For most people PyInstaller — it's the most popular, cross-platform, well-documented, and bundles everything into one file with a single command (auto-py-to-exe is just a GUI for it). If you want faster binaries and the strongest protection, Nuitka compiles Python to C machine code. cx_Freeze is a simpler freezer, and py2exe is a legacy Windows-only option.
How do I convert Python to EXE without PyInstaller?
Use Nuitka or cx_Freeze. Nuitka compiles your Python to C and then to a native binary — faster and much harder to reverse-engineer since there's no bytecode to extract, though it needs a C compiler and builds are slower. cx_Freeze is a simpler freezer that bundles bytecode plus the interpreter into a folder with the exe, similar to PyInstaller but without using it.
Is auto-py-to-exe different from PyInstaller?
Not really — auto-py-to-exe is a graphical front-end that runs PyInstaller under the hood. You get the same exe you'd get from the PyInstaller command line, just configured through a point-and-click UI. Choose it if you prefer not to use the terminal; the output and its limitations are identical to PyInstaller.
Does converting Python to an EXE protect my source code?
No. PyInstaller, cx_Freeze, py2exe and auto-py-to-exe bundle your .pyc bytecode, which extracts (e.g. with pyinstxtractor) and decompiles back to near-original source, with string literals like API keys in plain text. To protect code, obfuscate the source before building, keep secrets off the client, or use Nuitka, which compiles to machine code instead of shipping bytecode.
Why is my Python EXE so large?
Because these tools bundle the entire Python interpreter and your dependencies inside the executable, so even a tiny script becomes several megabytes — in a real test, a 921-byte script produced an ~8 MB PyInstaller exe. You can reduce size with options like UPX compression or by trimming unused modules, but a multi-megabyte baseline is normal for a self-contained Python exe.