Using PyInstaller

The syntax of the pyinstaller command is:

pyinstaller [options] script [script …] | specfile

In the most simple case, set the current directory to the location of your program and execute:


PyInstaller analyzes and:

  • Writes myscript.spec in the same folder as the script.

  • Creates a folder build in the same folder as the script if it does not exist.

  • Writes some log files and working files in the build folder.

  • Creates a folder dist in the same folder as the script if it does not exist.

  • Writes the myscript executable folder in the dist folder.

In the dist folder you find the bundled app you distribute to your users.

Normally you name one script on the command line. If you name more, all are analyzed and included in the output. However, the first script named supplies the name for the spec file and for the executable folder or file. Its code is the first to execute at run-time.

For certain uses you may edit the contents of myscript.spec (described under Using Spec Files). After you do this, you name the spec file to PyInstaller instead of the script:

pyinstaller myscript.spec

The myscript.spec file contains most of the information provided by the options that were specified when pyinstaller (or pyi-makespec) was run with the script file as the argument. You typically do not need to specify any options when running pyinstaller with the spec file. Only a few command-line options have an effect when building from a spec file.

You may give a path to the script or spec file, for example

pyinstaller options… ~/myproject/source/

or, on Windows,

pyinstaller "C:\Documents and Settings\project\myscript.spec"


A full list of the pyinstaller command’s options are as follows:

Positional Arguments


Name of scriptfiles to be processed or exactly one .spec file. If a .spec file is specified, most options are unnecessary and are ignored.

Optional Arguments

-h, --help

show this help message and exit

-v, --version

Show program version info and exit.

--distpath DIR

Where to put the bundled app (default: ./dist)

--workpath WORKPATH

Where to put all the temporary work files, .log, .pyz and etc. (default: ./build)

-y, --noconfirm

Replace output directory (default: SPECPATH/dist/SPECNAME) without asking for confirmation

--upx-dir UPX_DIR

Path to UPX utility (default: search the execution path)

-a, --ascii

Do not include unicode encoding support (default: included if available)


Clean PyInstaller cache and remove temporary files before building.

--log-level LEVEL

Amount of detail in build-time console messages. LEVEL may be one of TRACE, DEBUG, INFO, WARN, ERROR, CRITICAL (default: INFO).

What To Generate

-D, --onedir

Create a one-folder bundle containing an executable (default)

-F, --onefile

Create a one-file bundled executable.

--specpath DIR

Folder to store the generated spec file (default: current directory)

-n NAME, --name NAME

Name to assign to the bundled app and spec file (default: first script’s basename)

How To Generate

-d {all,imports,bootloader,noarchive}, --debug {all,imports,bootloader,noarchive}

Provide assistance with debugging a frozen application. This argument may be provided multiple times to select several of the following options. - all: All three of the following options. - imports: specify the -v option to the underlying Python interpreter, causing it to print a message each time a module is initialized, showing the place (filename or built-in module) from which it is loaded. See - bootloader: tell the bootloader to issue progress messages while initializing and starting the bundled app. Used to diagnose problems with missing imports. - noarchive: instead of storing all frozen Python source files as an archive inside the resulting executable, store them as files in the resulting output directory.

--python-option PYTHON_OPTION

Specify a command-line option to pass to the Python interpreter at runtime. Currently supports “v” (equivalent to “–debug imports”), “u”, and “W <warning control>”.

-s, --strip

Apply a symbol-table strip to the executable and shared libs (not recommended for Windows)


Do not use UPX even if it is available (works differently between Windows and *nix)

--upx-exclude FILE

Prevent a binary from being compressed when using upx. This is typically used if upx corrupts certain binaries during compression. FILE is the filename of the binary without path. This option can be used multiple times.

Windows And Mac Os X Specific Options

-c, --console, --nowindowed

Open a console window for standard i/o (default). On Windows this option has no effect if the first script is a ‘.pyw’ file.

-w, --windowed, --noconsole

Windows and Mac OS X: do not provide a console window for standard i/o. On Mac OS this also triggers building a Mac OS .app bundle. On Windows this option is automatically set if the first script is a ‘.pyw’ file. This option is ignored on *NIX systems.

-i <FILE.ico or FILE.exe,ID or FILE.icns or "NONE">, --icon <FILE.ico or FILE.exe,ID or FILE.icns or "NONE">

FILE.ico: apply the icon to a Windows executable. FILE.exe,ID: extract the icon with ID from an exe. FILE.icns: apply the icon to the .app bundle on Mac OS. Use “NONE” to not apply any icon, thereby making the OS to show some default (default: apply PyInstaller’s icon)


Disable traceback dump of unhandled exception in windowed (noconsole) mode (Windows and macOS only), and instead display a message that this feature is disabled.

Windows Specific Options

--version-file FILE

Add a version resource from FILE to the exe.

-m <FILE or XML>, --manifest <FILE or XML>

Add manifest FILE or XML to the exe.


Generate an external .exe.manifest file instead of embedding the manifest into the exe. Applicable only to onedir mode; in onefile mode, the manifest is always embedded, regardless of this option.

-r RESOURCE, --resource RESOURCE

Add or update a resource to a Windows executable. The RESOURCE is one to four items, FILE[,TYPE[,NAME[,LANGUAGE]]]. FILE can be a data file or an exe/dll. For data files, at least TYPE and NAME must be specified. LANGUAGE defaults to 0 or may be specified as wildcard * to update all resources of the given TYPE and NAME. For exe/dll files, all resources from FILE will be added/updated to the final executable if TYPE, NAME and LANGUAGE are omitted or specified as wildcard *. This option can be used multiple times.


Using this option creates a Manifest that will request elevation upon application start.


Using this option allows an elevated application to work with Remote Desktop.

Windows Side-By-Side Assembly Searching Options (Advanced)


Any Shared Assemblies bundled into the application will be changed into Private Assemblies. This means the exact versions of these assemblies will always be used, and any newer versions installed on user machines at the system level will be ignored.


While searching for Shared or Private Assemblies to bundle into the application, PyInstaller will prefer not to follow policies that redirect to newer versions, and will try to bundle the exact versions of the assembly.

Mac Os Specific Options

--osx-bundle-identifier BUNDLE_IDENTIFIER

Mac OS .app bundle identifier is used as the default unique program name for code signing purposes. The usual form is a hierarchical name in reverse DNS notation. For example: com.mycompany.department.appname (default: first script’s basename)

--target-architecture ARCH, --target-arch ARCH

Target architecture (macOS only; valid values: x86_64, arm64, universal2). Enables switching between universal2 and single-arch version of frozen application (provided python installation supports the target architecture). If not target architecture is not specified, the current running architecture is targeted.

--codesign-identity IDENTITY

Code signing identity (macOS only). Use the provided identity to sign collected binaries and generated executable. If signing identity is not provided, ad- hoc signing is performed instead.

--osx-entitlements-file FILENAME

Entitlements file to use when code-signing the collected binaries (macOS only).

Rarely Used Special Options

--runtime-tmpdir PATH

Where to extract libraries and support files in onefile-mode. If this option is given, the bootloader will ignore any temp-folder location defined by the run-time OS. The _MEIxxxxxx-folder will be created here. Please use this option only if you know what you are doing.


Tell the bootloader to ignore signals rather than forwarding them to the child process. Useful in situations where for example a supervisor process signals both the bootloader and the child (e.g., via a process group) to avoid signalling the child twice.

Shortening the Command

Because of its numerous options, a full pyinstaller command can become very long. You will run the same command again and again as you develop your script. You can put the command in a shell script or batch file, using line continuations to make it readable. For example, in GNU/Linux:

pyinstaller --noconfirm --log-level=WARN \
    --onefile --nowindow \
    --add-data="README:." \
    --add-data="image1.png:img" \
    --add-binary="" \
    --hidden-import=secret1 \
    --hidden-import=secret2 \
    --upx-dir=/usr/local/share/ \

Or in Windows, use the little-known BAT file line continuation:

pyinstaller --noconfirm --log-level=WARN ^
    --onefile --nowindow ^
    --add-data="README;." ^
    --add-data="image1.png;img" ^
    --add-binary=";lib" ^
    --hidden-import=secret1 ^
    --hidden-import=secret2 ^
    --icon=..\MLNMFLCN.ICO ^

Running PyInstaller from Python code

If you want to run PyInstaller from Python code, you can use the run function defined in PyInstaller.__main__. For instance, the following code:

import PyInstaller.__main__[

Is equivalent to:

pyinstaller --onefile --windowed

Using UPX

UPX is a free utility available for most operating systems. UPX compresses executable files and libraries, making them smaller, sometimes much smaller. UPX is available for most operating systems and can compress a large number of executable file formats. See the UPX home page for downloads, and for the list of supported executable formats.

A compressed executable program is wrapped in UPX startup code that dynamically decompresses the program when the program is launched. After it has been decompressed, the program runs normally. In the case of a PyInstaller one-file executable that has been UPX-compressed, the full execution sequence is:

  • The compressed program start up in the UPX decompressor code.

  • After decompression, the program executes the PyInstaller bootloader, which creates a temporary environment for Python.

  • The Python interpreter executes your script.

PyInstaller looks for UPX on the execution path or the path specified with the --upx-dir option. If UPX exists, PyInstaller applies it to the final executable, unless the --noupx option was given. UPX has been used with PyInstaller output often, usually with no problems.

Encrypting Python Bytecode

To encrypt the Python bytecode modules stored in the bundle, pass the --key=key-string argument on the command line.

For this to work, you need to run:

pip install pyinstaller[encryption]

The key-string is a string of 16 characters which is used to encrypt each file of Python byte-code before it is stored in the archive inside the executable file.

This feature uses the tinyaes module internally for the encryption.

Splash Screen (Experimental)


This feature is incompatible with macOS. In the current design, the splash screen operates in a secondary thread, which is disallowed by the Tcl/Tk (or rather, the underlying GUI toolkit) on macOS.

Some applications may require a splash screen as soon as the application (bootloader) has been started, because especially in onefile mode large applications may have long extraction/startup times, while the bootloader prepares everything, where the user cannot judge whether the application was started successfully or not.

The bootloader is able to display a one-image (i.e. only an image) splash screen, which is displayed before the actual main extraction process starts. The splash screen supports non-transparent and hard-cut-transparent images as background image, so non-rectangular splash screens can also be displayed.

This splash screen is based on Tcl/Tk, which is the same library used by the Python module tkinter. PyInstaller bundles the dynamic libraries of tcl and tk into the application at compile time. These are loaded into the bootloader at startup of the application after they have been extracted (if the program has been packaged as an onefile archive). Since the file sizes of the necessary dynamic libraries are very small, there is almost no delay between the start of the application and the splash screen. The compressed size of the files necessary for the splash screen is about 1.5 MB.

As an additional feature, text can optionally be displayed on the splash screen. This can be changed/updated from within Python. This offers the possibility to display the splash screen during longer startup procedures of a Python program (e.g. waiting for a network response or loading large files into memory). You can also start a GUI behind the splash screen, and only after it is completely initialized the splash screen can be closed. Optionally, the font, color and size of the text can be set. However, the font must be installed on the user system, as it is not bundled. If the font is not available, a fallback font is used.

If the splash screen is configured to show text, it will automatically (as onefile archive) display the name of the file that is currently being unpacked, this acts as a progress bar.

The pyi_splash Module

The splash screen is controlled from within Python by the pyi_splash module, which can be imported at runtime. This module cannot be installed by a package manager because it is part of PyInstaller and is included as needed. This module must be imported within the Python program. The usage is as follows:

import pyi_splash

# Update the text on the splash screen
pyi_splash.update_text("PyInstaller is a great software!")
pyi_splash.update_text("Second time's a charm!")

# Close the splash screen. It does not matter when the call
# to this function is made, the splash screen remains open until
# this function is called or the Python program is terminated.

Of course the import should be in a try ... except block, in case the program is used externally as a normal Python script, without a bootloader. For a detailed description see pyi_splash Module (Detailed).

Defining the Extraction Location

In rare cases, when you bundle to a single executable (see Bundling to One File and How the One-File Program Works), you may want to control the location of the temporary directory at compile time. This can be done using the --runtime-tmpdir option. If this option is given, the bootloader will ignore any temp-folder location defined by the run-time OS. Please use this option only if you know what you are doing.

Supporting Multiple Platforms

If you distribute your application for only one combination of OS and Python, just install PyInstaller like any other package and use it in your normal development setup.

Supporting Multiple Python Environments

When you need to bundle your application within one OS but for different versions of Python and support libraries – for example, a Python 3.6 version and a Python 3.7 version; or a supported version that uses Qt4 and a development version that uses Qt5 – we recommend you use venv. With venv you can maintain different combinations of Python and installed packages, and switch from one combination to another easily. These are called virtual environments or venvs in short.

  • Use venv to create as many different development environments as you need, each with its unique combination of Python and installed packages.

  • Install PyInstaller in each virtual environment.

  • Use PyInstaller to build your application in each virtual environment.

Note that when using venv, the path to the PyInstaller commands is:

  • Windows: ENV_ROOT\Scripts

  • Others: ENV_ROOT/bin

Under Windows, the pip-Win package makes it especially easy to set up different environments and switch between them. Under GNU/Linux and Mac OS, you switch environments at the command line.

See PEP 405 and the official Python Tutorial on Virtual Environments and Packages for more information about Python virtual environments.

Supporting Multiple Operating Systems

If you need to distribute your application for more than one OS, for example both Windows and Mac OS X, you must install PyInstaller on each platform and bundle your app separately on each.

You can do this from a single machine using virtualization. The free virtualBox or the paid VMWare and Parallels allow you to run another complete operating system as a “guest”. You set up a virtual machine for each “guest” OS. In it you install Python, the support packages your application needs, and PyInstaller.

A File Sync & Share system like NextCloud is useful with virtual machines. Install the synchronization client in each virtual machine, all linked to your synchronization account. Keep a single copy of your script(s) in a synchronized folder. Then on any virtual machine you can run PyInstaller thus:

cd ~/NextCloud/project_folder/src # GNU/Linux, Mac -- Windows similar
rm *.pyc # get rid of modules compiled by another Python
pyinstaller --workpath=path-to-local-temp-folder  \
            --distpath=path-to-local-dist-folder  \
            ...other options as required...       \

PyInstaller reads scripts from the common synchronized folder, but writes its work files and the bundled app in folders that are local to the virtual machine.

If you share the same home directory on multiple platforms, for example GNU/Linux and OS X, you will need to set the PYINSTALLER_CONFIG_DIR environment variable to different values on each platform otherwise PyInstaller may cache files for one platform and use them on the other platform, as by default it uses a subdirectory of your home directory as its cache location.

It is said to be possible to cross-develop for Windows under GNU/Linux using the free Wine environment. Further details are needed, see How to Contribute.

Capturing Windows Version Data

A Windows app may require a Version resource file. A Version resource contains a group of data structures, some containing binary integers and some containing strings, that describe the properties of the executable. For details see the Microsoft Version Information Structures page.

Version resources are complex and some elements are optional, others required. When you view the version tab of a Properties dialog, there’s no simple relationship between the data displayed and the structure of the resource. For this reason PyInstaller includes the pyi-grab_version command. It is invoked with the full path name of any Windows executable that has a Version resource:

pyi-grab_version executable_with_version_resource

The command writes text that represents a Version resource in readable form to standard output. You can copy it from the console window or redirect it to a file. Then you can edit the version information to adapt it to your program. Using pyi-grab_version you can find an executable that displays the kind of information you want, copy its resource data, and modify it to suit your package.

The version text file is encoded UTF-8 and may contain non-ASCII characters. (Unicode characters are allowed in Version resource string fields.) Be sure to edit and save the text file in UTF-8 unless you are certain it contains only ASCII string values.

Your edited version text file can be given with the --version-file option to pyinstaller or pyi-makespec. The text data is converted to a Version resource and installed in the bundled app.

In a Version resource there are two 64-bit binary values, FileVersion and ProductVersion. In the version text file these are given as four-element tuples, for example:

filevers=(2, 0, 4, 0),
prodvers=(2, 0, 4, 0),

The elements of each tuple represent 16-bit values from most-significant to least-significant. For example the value (2, 0, 4, 0) resolves to 0002000000040000 in hex.

You can also install a Version resource from a text file after the bundled app has been created, using the pyi-set_version command:

pyi-set_version version_text_file executable_file

The pyi-set_version utility reads a version text file as written by pyi-grab_version, converts it to a Version resource, and installs that resource in the executable_file specified.

For advanced uses, examine a version text file as written by pyi-grab_version. You find it is Python code that creates a VSVersionInfo object. The class definition for VSVersionInfo is found in utils/win32/ in the PyInstaller distribution folder. You can write a program that imports versioninfo. In that program you can eval the contents of a version info text file to produce a VSVersionInfo object. You can use the .toRaw() method of that object to produce a Version resource in binary form. Or you can apply the unicode() function to the object to reproduce the version text file.

Building Mac OS X App Bundles

Under Mac OS X, PyInstaller always builds a UNIX executable in dist. If you specify --onedir, the output is a folder named myscript containing supporting files and an executable named myscript. If you specify --onefile, the output is a single UNIX executable named myscript. Either executable can be started from a Terminal command line. Standard input and output work as normal through that Terminal window.

If you specify --windowed with either option, the dist folder also contains an OS X application named

As you probably know, an application is a special type of folder. The one built by PyInstaller contains a folder always named Contents which contains:

  • A folder Frameworks which is empty.

  • A folder Resources that contains an icon file.

  • A file Info.plist that describes the app.

  • A folder MacOS that contains the the executable and supporting files, just as in the --onedir folder.

Use the --icon argument to specify a custom icon for the application. It will be copied into the Resources folder. (If you do not specify an icon file, PyInstaller supplies a file icon-windowed.icns with the PyInstaller logo.)

Use the --osx-bundle-identifier argument to add a bundle identifier. This becomes the CFBundleIdentifier used in code-signing (see the PyInstaller code signing recipe and for more detail, the Apple code signing overview technical note).

You can add other items to the Info.plist by editing the spec file; see Spec File Options for a Mac OS X Bundle below.

Platform-specific Notes


Making GNU/Linux Apps Forward-Compatible

Under GNU/Linux, PyInstaller does not bundle libc (the C standard library, usually glibc, the Gnu version) with the app. Instead, the app expects to link dynamically to the libc from the local OS where it runs. The interface between any app and libc is forward compatible to newer releases, but it is not backward compatible to older releases.

For this reason, if you bundle your app on the current version of GNU/Linux, it may fail to execute (typically with a runtime dynamic link error) if it is executed on an older version of GNU/Linux.

The solution is to always build your app on the oldest version of GNU/Linux you mean to support. It should continue to work with the libc found on newer versions.

The GNU/Linux standard libraries such as glibc are distributed in 64-bit and 32-bit versions, and these are not compatible. As a result you cannot bundle your app on a 32-bit system and run it on a 64-bit installation, nor vice-versa. You must make a unique version of the app for each word-length supported.


The developer needs to take special care to include the Visual C++ run-time .dlls: Python 3.5+ uses Visual Studio 2015 run-time, which has been renamed into “Universal CRT“ and has become part of Windows 10. For Windows Vista through Windows 8.1 there are Windows Update packages, which may or may not be installed in the target-system. So you have the following options:

  1. Build on Windows 7 which has been reported to work.

  2. Include one of the VCRedist packages (the redistributable package files) into your application’s installer. This is Microsoft’s recommended way, see “Distributing Software that uses the Universal CRT“ in the above-mentioned link, numbers 2 and 3.

  3. Install the Windows Software Development Kit (SDK) for Windows 10 and expand the .spec-file to include the required DLLs, see “Distributing Software that uses the Universal CRT“ in the above-mentioned link, number 6.

    If you think, PyInstaller should do this by itself, please help improving PyInstaller.

Mac OS X

Making Mac OS X apps Forward-Compatible

In Mac OS X, components from one version of the OS are usually compatible with later versions, but they may not work with earlier versions.

The only way to be certain your app supports an older version of Mac OS X is to run PyInstaller in the oldest version of the OS you need to support.

For example, to be sure of compatibility with “Snow Leopard” (10.6) and later versions, you should execute PyInstaller in that environment. You would create a copy of Mac OS X 10.6, typically in a virtual machine. In it, install the desired level of Python (the default Python in Snow Leopard was 2.6, which PyInstaller no longer supports), and install PyInstaller, your source, and all its dependencies. Then build your app in that environment. It should be compatible with later versions of Mac OS X.

Building 32-bit Apps in Mac OS X


This section still refers to Python 2.7 provided by Apple. It might not be valid for Python 3 installed from MacPorts or Homebrew.

Please contribute to keep this section up-to-date.

Older versions of Mac OS X supported both 32-bit and 64-bit executables. PyInstaller builds an app using the the word-length of the Python used to execute it. That will typically be a 64-bit version of Python, resulting in a 64-bit executable. To create a 32-bit executable, run PyInstaller under a 32-bit Python.

Python as installed in OS X will usually be executable in either 64- or 32-bit mode. To verify this, apply the file command to the Python executable:

$ file /usr/local/bin/python3
/usr/local/bin/python3: Mach-O universal binary with 2 architectures
/usr/local/bin/python3 (for architecture i386):     Mach-O executable i386
/usr/local/bin/python3 (for architecture x86_64):   Mach-O 64-bit executable x86_64

The OS chooses which architecture to run, and typically defaults to 64-bit. You can force the use of either architecture by name using the arch command:

$ /usr/local/bin/python3
Python 3.4.2 (v3.4.2:ab2c023a9432, Oct  5 2014, 20:42:22)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys; sys.maxsize

$ arch -i386 /usr/local/bin/python3
Python 3.4.2 (v3.4.2:ab2c023a9432, Oct  5 2014, 20:42:22)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys; sys.maxsize

Apple’s default /usr/bin/python may circumvent the arch specification and run 64-bit regardless. (That is not the case if you apply arch to a specific version such as /usr/bin/python2.7.) To make sure of running 32-bit in all cases, set the following environment variable:

arch -i386 /usr/bin/python pyinstaller --clean -F -w

Getting the Opened Document Names


Support for OpenDocument events is broken in PyInstaller 3.0 owing to code changes needed in the bootloader to support current versions of Mac OS X. Do not attempt to use this feature until it has been fixed. If this feature is important to you, follow and comment on the status of PyInstaller Issue #1309.

When a user double-clicks a document of a type your application supports, or when a user drags a document icon and drops it on your application’s icon, Mac OS X launches your application and provides the name(s) of the opened document(s) in the form of an OpenDocument AppleEvent. This AppleEvent is received by the bootloader before your code has started executing.

The bootloader gets the names of opened documents from the OpenDocument event and encodes them into the argv string before starting your code. Thus your code can query sys.argv to get the names of documents that should be opened at startup.

OpenDocument is the only AppleEvent the bootloader handles. If you want to handle other events, or events that are delivered after the program has launched, you must set up the appropriate handlers.


Depending on whether Python was build as a 32-bit or a 64-bit executable you may need to set or unset the environment variable OBJECT_MODE. To determine the size the following command can be used:

$ python -c "import sys; print(sys.maxsize <= 2**32)"

When the answer is True (as above) Python was build as a 32-bit executable.

When working with a 32-bit Python executable proceed as follows:

$ pyinstaller <your arguments>

When working with a 64-bit Python executable proceed as follows:

$ export OBJECT_MODE=64
$ pyinstaller <your arguments>