The first release candidate for Python 3.14 has been released, featuring new features such as free-threaded Python, deferred evaluation of type annotations, template string literals, multiple interpreters in stdlib, compression.zstd, except and except* expressions, syntax highlighting in PyREPL, a zero-overhead external debugger interface for CPython, support for UUID versions 6-8, and a new C API for configuring Python. It also includes improved error messages, built-in implementation of HMAC, and a new command-line interface for inspecting running Python processes.

Python Insider: Python 3.14 release candidate 1 is go!

It’s the first 3.14 release candidate!

https://www.python.org/downloads/release/python-3140rc1/

This is the first release candidate of Python 3.14

This release, 3.14.0rc1, is the penultimate release preview. Entering the release candidate phase, only reviewed code changes which are clear bug fixes are allowed between this release candidate and the final release. The second candidate (and the last planned release preview) is scheduled for Tuesday, 2025-08-26, while the official release of 3.14.0 is scheduled for Tuesday, 2025-10-07.

There will be no ABI changes from this point forward in the 3.14 series, and the goal is that there will be as few code changes as possible.

Major new features of the 3.14 series, compared to 3.13

Some of the major new features and changes in Python 3.14 are:

New features

• PEP 779: Free-threaded Python is officially supported
• PEP 649: The evaluation of type annotations is now deferred, improving the semantics of using annotations.
• PEP 750: Template string literals (t-strings) for custom string processing, using the familiar syntax of f-strings.
• PEP 734: Multiple interpreters in the stdlib.
• PEP 784: A new module compression.zstd providing support for the Zstandard compression algorithm.
• PEP 758: except and except* expressions may now omit the brackets.
• Syntax highlighting in PyREPL, and support for color in  unittest,  argparse,  json and  calendar CLIs.
• PEP 768: A zero-overhead external debugger interface for CPython.
• UUID versions 6-8 are now supported by the uuid module, and generation of versions 3-5 are up to 40% faster.
• PEP 765: Disallow return/break/continue that exit a finally block.
• PEP 741: An improved C API for configuring Python.
• A  new type of interpreter. For certain newer compilers, this interpreter provides significantly better performance. Opt-in for now, requires building from source.
• Improved error messages.
• Builtin implementation of HMAC with formally verified code from the HACL* project.
• A  new command-line interface to inspect running Python processes using asynchronous tasks.
• The pdb module now supports  remote attaching to a running Python process.

(Hey, fellow core developer, if a feature you find important is missing from this list, let Hugo know.)

For more details on the changes to Python 3.14, see  What’s new in Python 3.14. The next pre-release of Python 3.14 will be the final release candidate, 3.14.0rc2, scheduled for 2025-08-26.

Python Insider: Python 3.14 release candidate 1 is go!