According to the What's new in Python 3.13, you need a new Python binary to test it.
The free-threaded mode requires a different executable, usually called python3.13t or python3.13t.exe.
Using pyenv latest version to install Python, this should give you a virtual environment to test it (in most unix systems):
pyenv install 3.13t-dev
$HOME/.pyenv/versions/3.13t-dev/bin/python3.13t -m venv .venv
source .venv/bin/activate
You can check it with sys._is_gil_enabled()
python -c 'import sys; print(sys._is_gil_enabled())'
# you should get 'False'
Top answer 1 of 3
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According to the What's new in Python 3.13, you need a new Python binary to test it.
The free-threaded mode requires a different executable, usually called python3.13t or python3.13t.exe.
Using pyenv latest version to install Python, this should give you a virtual environment to test it (in most unix systems):
pyenv install 3.13t-dev
$HOME/.pyenv/versions/3.13t-dev/bin/python3.13t -m venv .venv
source .venv/bin/activate
You can check it with sys._is_gil_enabled()
python -c 'import sys; print(sys._is_gil_enabled())'
# you should get 'False'
2 of 3
2
Ubunt users can use:
sudo add-apt-repository ppa:deadsnakes
sudo apt-get update
sudo apt-get install python3.13-nogil
Reddit
reddit.com › r/programming › disabling gil in python 3.13
r/programming on Reddit: Disabling GIL in Python 3.13
October 10, 2024 - What's up, Python? The GIL removed, a new compiler, optparse deprecated...
Videos
10:00
How Much FASTER Is Python 3.13 Without the GIL? - YouTube
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How to get started with Python 3.13's free-threading |"no-GIL" ...
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How to Disable GIL in Python3.13 | Free-threaded Python | 2MinutesPy ...
06:02
Python Without GIL? Discover the Free-Threaded Mode in Python 3.13 ...
08:45
Python 3.13 release: bye GIL, hi JIT, new REPL! - YouTube
Medium
medium.com › @mitesh.singh.jat › gil-becomes-optional-in-python-3-13-a-game-changer-for-multithreading-4c5d28856803
GIL Becomes Optional in Python 3.13: A Game-Changer for Multithreading! | by Mitesh Singh Jat | Medium
August 14, 2024 - In the world of programming, concurrency is a crucial aspect to improve the performance of your applications. In Python, the Global Interpreter Lock (GIL) has been a major hurdle in achieving true concurrency. However, with the upcoming release of Python 3.13, the GIL becomes optional!
Reddit
reddit.com › r/programming › gil become optional in python 3.13
r/programming on Reddit: GIL Become Optional in Python 3.13
August 12, 2024 - This is not correct, the GIL lock applies to instructions at the interpreter level and not in python code. Foo can be removed after the check or even between getting its value and incrementing it in python code without mutexes or locks
Reddit
reddit.com › r/programming › what's up, python? the gil removed, a new compiler, optparse deprecated...
r/programming on Reddit: What's up, Python? The GIL removed, a new compiler, optparse deprecated...
March 13, 2024 - Article from July 2023. PEP-703 was formally accepted in October. Disabling the GIL landed in Python 3.13 with a —disable-gil flag.
Flyaps
flyaps.com › the first ever no-gil python: what’s new in python 3.13?
The First Ever No-GIL Python: What’s New in Python 3.13?
September 29, 2025 - Therefore, I disagree with those who say that the GIL is terrible and should never have been added. No, I don't think so. The reason Python became successful is that it has the GIL." Eight years on from those remarks, it is clear that Python is moving towards the removal of the GIL.
DEV Community
dev.to › basilemarchand › benchmarks-of-python-314b2-with-disable-gil-1ml3
🚀 Benchmarks of Python 3.14b2 with --disable-gil - DEV Community
June 11, 2025 - This is the subject of PEP 703 ... it is possible to allow disabling the GIL — for this, the Python interpreter must be compiled with the --disable-gil option....
Medium
medium.com › coinmonks › pythons-gil-is-finally-dead-f57edf9c99a3
Python’s GIL is finally Dead. What Changed in 3.13–3.14, and How It… | by Sweety Tripathi | Coinmonks | Medium
October 28, 2025 - Why I am talking about this ?Python 3.13+ is introducing a revolutionary ability to disable the GIL, representing one of the most significant internal changes in the language’s history especially for engineers in AI, data science, and ...
Mouse Vs Python
blog.pythonlibrary.org › home › python 3.13 allows disabling of the gil + subinterpreters
Python 3.13 Allows Disabling of the GIL + subinterpreters - Mouse Vs Python
March 14, 2024 - Python 3.13 adds the ability to remove the Global Interpreter Lock (GIL) per PEP 703. Just this past week, a PR was merged in that allows the disabling of
Python
peps.python.org › pep-0703
PEP 703 – Making the Global Interpreter Lock Optional in CPython | peps.python.org
The --disable-gil builds of CPython will still support optionally running with the GIL enabled at runtime (see PYTHONGIL Environment Variable and Py_mod_gil Slot). Removing the global interpreter lock requires substantial changes to CPython internals, but relatively few changes to the public Python and C APIs.
Reddit
reddit.com › r/programming › python is removing gil, gradually, so how to use a no-gil python now?
r/programming on Reddit: Python is removing GIL, gradually, so how to use a no-GIL Python now?
June 15, 2025 - I think they laid the team off because they weren't making much progress. Python may improve in the future, but I certainly wouldn't base any decisions today off of theoretical efficiency gains in the future.
DEV Community
dev.to › epam_india_python › python-313-the-gateway-to-high-performance-multithreading-without-gil-1dm7
Python 3.13: The Gateway to High-Performance Multithreading Without GIL - DEV Community
January 6, 2025 - To disable the GIL using the -X gil=0 flag, you need to compile Python from source with the --disable-gil flag enabled. Here's how to do that · Download Python 3.13 Source Code You first need to download the Python 3.13 source code tarball ...
Geek Python
geekpython.in › how-to-disable-gil-in-python
How to Disable GIL in Python 3.13?
October 10, 2024 - First, download the official Python 3.13 on your local machine. Then proceed to install the Python executable file. Follow the steps just as you install any Python version, you will see a step in which you are asked to choose the advanced installation options. Now select the checkbox appearing at the end, this will install the different executable Python build with the name python3.13t or python3.13t.exe. This will allow you to optionally disable or enable GIL in the runtime.
JetBrains
blog.jetbrains.com › pycharm › 2025 › 07 › faster-python-unlocking-the-python-global-interpreter-lock
Faster Python: Unlocking the Python Global Interpreter Lock | The PyCharm Blog
December 18, 2025 - Python has not removed the GIL, but PEP 703 makes it optional and introduces a free-threaded build in Python 3.13. The standard build still uses the GIL, and this will remain the case until the ecosystem fully supports free-threaded operation.
Python documentation
docs.python.org › 3 › whatsnew › 3.13.html
What’s New In Python 3.13
February 24, 2026 - CPython now has experimental support for running in a free-threaded mode, with the global interpreter lock (GIL) disabled. This is an experimental feature and therefore is not enabled by default. The free-threaded mode requires a different executable, usually called python3.13t or python3.13t.exe.
Medium
medium.com › @surajbahuguna1 › python-3-13-is-here-and-the-gil-is-almost-gone-fea223df4faf
Python 3.13 is Here, and the GIL is (Almost) Gone! | by Suraj (IIT Delhi) | Medium
October 14, 2024 - Python 3.13 has arrived, and with it, a game-changing feature that has long been the subject of heated discussions in the developer community: the removal of the Global Interpreter Lock (GIL). Yes, you read that right! The GIL-free Python era has finally begun, and it’s opening the door to true multi-threading, something developers have craved for years.
Towards Data Science
towardsdatascience.com › home › latest › python 3.14 and the end of the gil
Python 3.14 and the End of the GIL | Towards Data Science
October 18, 2025 - In this article, we discuss a potentially groundbreaking feature of the latest Python 3.14 release: the introduction of an optional “free-threaded” version, which removes the Global Interpreter Lock (GIL). The GIL is a mechanism in standard Python that simplifies memory management by ensuring only one thread executes Python bytecode at a time.
Writings
hemachandra.hashnode.dev › disabling-gil-nogil-in-python
Disabling GIL in Python, How to use Python without GIL, NoGIL
January 4, 2025 - If you are building from scratch, make sure you include the --disable-gil option during installation for the free threading build. After installing Python 3.13, check the installation folder (e.g., C:\Program Files\Python313).
LinkedIn
linkedin.com › posts › danlorenc_progress-on-no-gil-cpython-activity-7122184950413414400-5F_u
New effort to remove GIL in Python 3.13 | Dan Lorenc posted on the topic | LinkedIn
October 23, 2023 - The often-maligned Global Interpreter Lock (GIL) might be removed in Python 3.13! The GIL has been around in Python from the early days, and has often been criticized for reducing the performance of Python programs.