# charset_normalizer changelog

> charset_normalizer release notes.

- Vendor: charset_normalizer
- Category: Frameworks & Libraries
- Official site: https://github.com/jawah/charset_normalizer
- Tracked by: What's New (https://whatsnew.fyi/product/charset-normalizer)
- Harvested from: GitHub (jawah/charset_normalizer)
- Entries below: 10 (newest first)

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

## Releases

### 3.4.9 — Version 3.4.9

- Date: 2026-07-07
- Version: 3.4.9
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.9
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.9

###### Fixed
- Regression in our fallback path leading to a decode error. (#771)
  We've yanked 3.4.8 as a result of that bug.

### 3.4.8 — Version 3.4.8

- Date: 2026-07-06
- Version: 3.4.8
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.8
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.8

##### [3.4.8](https://github.com/Ousret/charset_normalizer/compare/3.4.7...3.4.8) (2026-07-06)

###### Fixed
- Wall import time due to cascade codec imports for our multibyte first sort of iana supported codecs (#742)
- Unnecessary json import at runtime (#753)
- Inverse capitalization not seen by noise detector (#731)

###### Changed
- No longer holding a global cache for our noise / coherence measurements. Relax RSS memory usage.
- Micro-optimizations in our noise / coherence measurements.
- No longer using regex search by default for our preemptive charset mark algorithm.
- Raised upperbound of setuptools to v83.
- Raised upperbound of mypy(c) to v2.1.

###### Removed
- Redundant UTF7 BOM marker (#730)

### 3.4.7 — Version 3.4.7

- Date: 2026-04-02
- Version: 3.4.7
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.7
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.7

##### [3.4.7](https://github.com/Ousret/charset_normalizer/compare/3.4.6...3.4.7) (2026-04-02)

###### Changed
- Pre-built optimized version using mypy[c] v1.20.
- Relax `setuptools` constraint to `setuptools>=68,<82.1`.

###### Fixed
- Correctly remove SIG remnant in utf-7 decoded string. (#718) (#716)

### 3.4.6 — Version 3.4.6

- Date: 2026-03-15
- Version: 3.4.6
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.6
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.6

##### [3.4.6](https://github.com/Ousret/charset_normalizer/compare/3.4.5...3.4.6) (2026-03-15)

###### Changed
- Flattened the logic in `charset_normalizer.md` for higher performance. Removed `eligible(..)` and `feed(...)`
  in favor of `feed_info(...)`.
- Raised upper bound for mypy[c] to 1.20, for our optimized version.
- Updated `UNICODE_RANGES_COMBINED` using Unicode blocks v17.

###### Fixed
- Edge case where noise difference between two candidates can be almost insignificant. (#672)
- CLI `--normalize` writing to wrong path when passing multiple files in. (#702)

###### Misc
- Freethreaded pre-built wheels now shipped in PyPI starting with 3.14t. (#616)

### 3.4.5 — Version 3.4.5

- Date: 2026-03-06
- Version: 3.4.5
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.5
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.5

##### [3.4.5](https://github.com/Ousret/charset_normalizer/compare/3.4.4...3.4.5) (2026-03-06)

###### Changed
- Update `setuptools` constraint to `setuptools>=68,<=82`.
- Raised upper bound of mypyc for the optional pre-built extension to v1.19.1

###### Fixed
- Add explicit link to lib math in our optimized build. (#692)
- Logger level not restored correctly for empty byte sequences. (#701)
- TypeError when passing bytearray to from_bytes. (#703)

###### Misc
- Applied safe micro-optimizations in both our noise detector and language detector.
- Rewrote the `query_yes_no` function (inside CLI) to avoid using ambiguous licensed code.
- Added `cd.py` submodule into mypyc optional compilation to reduce further the performance impact.

> [!WARNING]  
> mypyc changed the usual binary output for the optimized wheel. Beware, especially if using PyInstaller or alike. See https://github.com/jawah/charset_normalizer/issues/714

### 3.4.4 — Version 3.4.4

- Date: 2025-10-14
- Version: 3.4.4
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.4
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.4

##### [3.4.4](https://github.com/Ousret/charset_normalizer/compare/3.4.3...3.4.4) (2025-10-13)

###### Changed
- Bound `setuptools` to a specific constraint `setuptools>=68,<=81`.
- Raised upper bound of mypyc for the optional pre-built extension to v1.18.2

###### Removed
- `setuptools-scm` as a build dependency.

###### Misc
- Enforced hashes in `dev-requirements.txt` and created `ci-requirements.txt` for security purposes.
- Additional pre-built wheels for riscv64, s390x, and armv7l architectures.
- Restore `multiple.intoto.jsonl` in GitHub releases in addition to individual attestation file per wheel.

### 3.4.3 — Version 3.4.3

- Date: 2025-08-09
- Version: 3.4.3
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.3
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.3

##### [3.4.3](https://github.com/Ousret/charset_normalizer/compare/3.4.2...3.4.3) (2025-08-09)

###### Changed
- mypy(c) is no longer a required dependency at build time if `CHARSET_NORMALIZER_USE_MYPYC` isn't set to `1`. (#595) (#583)
- automatically lower confidence on small bytes samples that are not Unicode in `detect` output legacy function. (#391)

###### Added
- Custom build backend to overcome inability to mark mypy as an optional dependency in the build phase.
- Support for Python 3.14

###### Fixed
- sdist archive contained useless directories.
- automatically fallback on valid UTF-16 or UTF-32 even if the md says it's noisy. (#633)

###### Misc
- SBOM are automatically published to the relevant GitHub release to comply with regulatory changes.
  Each published wheel comes with its SBOM. We choose CycloneDX as the format.
- Prebuilt optimized wheel are no longer distributed by default for CPython 3.7 due to a change in cibuildwheel.

### 3.4.2 — Version 3.4.2

- Date: 2025-05-02
- Version: 3.4.2
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.2
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.2

##### [3.4.2](https://github.com/Ousret/charset_normalizer/compare/3.4.1...3.4.2) (2025-05-02)

###### Fixed
- Addressed the DeprecationWarning in our CLI regarding `argparse.FileType` by backporting the target class into the package. (#591)
- Improved the overall reliability of the detector with CJK Ideographs. (#605) (#587)

###### Changed
- Optional mypyc compilation upgraded to version 1.15 for Python >= 3.9

### 3.4.1 — Version 3.4.1

- Date: 2024-12-24
- Version: 3.4.1
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.1
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.1

##### 🚀 We're still raising awareness around HTTP/2, and HTTP/3!

Did you know that Internet Explorer 11 shipped with an optional HTTP/2 support back in 2013? also libcurl did ship it in 2014[...]
Using Requests today is the rough equivalent of using EOL Windows 8!  We promptly invite Python developers to look at the first drop-in replacement for Requests, [namely Niquests](https://github.com/jawah/niquests). Ship with native WebSocket, SSE, Happy Eyeballs, DNS over HTTPS, and so on[...] All of this while remaining compatible with all Requests prior plug-ins / add-ons.

It leverages charset-normalizer in a better way! Check it out, you will gain up to being 3X faster and get a real/respectable support with it.

##### [3.4.1](https://github.com/Ousret/charset_normalizer/compare/3.4.0...3.4.1) (2024-12-24)

###### Changed
- Project metadata are now stored using `pyproject.toml` instead of `setup.cfg` using setuptools as the build backend.
- Enforce annotation delayed loading for a simpler and consistent types in the project.
- Optional mypyc compilation upgraded to version 1.14 for Python >= 3.8

###### Added
- pre-commit configuration.
- noxfile.

###### Removed
- `build-requirements.txt` as per using `pyproject.toml` native build configuration.
- `bin/integration.py` and `bin/serve.py` in favor of downstream integration test (see noxfile).
- `setup.cfg` in favor of `pyproject.toml` metadata configuration.
- Unused `utils.range_scan` function.

###### Fixed
- Converting content to Unicode bytes may insert `utf_8` instead of preferred `utf-8`. (#572)
- Deprecation warning "'count' is passed as positional argument" when converting to Unicode bytes on Python 3.13+

### 3.4.0 — Version 3.4.0

- Date: 2024-10-09
- Version: 3.4.0
- Original notes: https://github.com/jawah/charset_normalizer/releases/tag/3.4.0
- Permalink: https://whatsnew.fyi/product/charset-normalizer/releases/3.4.0

##### 🚀 charset-normalizer is raising awareness around HTTP/2, and HTTP/3!

Did you know that Internet Explorer 11 shipped with an optional HTTP/2 support back in 2013? also libcurl did ship it in 2014[...]
All of this while our community is still struggling to make a firm advancement in HTTP clients. Now, many of you use Requests
as the defacto http client, now, and for many years now, Requests has been frozen. Being left in a vegetative state and not evolving,
this blocked millions of developers from using more advanced features.

We promptly invite Python developers to look at the drop-in replacement for Requests, [namely Niquests](https://github.com/jawah/niquests).
It leverage charset-normalizer in a better way! Check it out, you will be positively surprised! Don't wait another decade.

We are thankful to @microsoft and involved parties for funding our work through the Microsoft FOSS Fund program.

##### [3.4.0](https://github.com/Ousret/charset_normalizer/compare/3.3.2...3.4.0) (2024-10-08)

###### Added
- Argument `--no-preemptive` in the CLI to prevent the detector to search for hints.
- Support for Python 3.13 (#512)

###### Fixed
- Relax the TypeError exception thrown when trying to compare a CharsetMatch with anything else than a CharsetMatch.
- Improved the general reliability of the detector based on user feedbacks. (#520) (#509) (#498) (#407) (#537)
- Declared charset in content (preemptive detection) not changed when converting to utf-8 bytes. (#381)