chardet

chardet [options] [file ...]
If no file arguments are provided, chardet reads from standard input.

file [file ...]
    Specifies one or more paths to the text files whose encoding needs to be detected. If omitted, chardet reads from standard input.

-h, --help
    Displays a brief help message detailing command usage and available options, then exits.

--version
    Outputs the program's version number and exits.

chardet is a command-line utility that leverages the powerful chardet Python library, which in turn is based on Mozilla's UniversalCharDet project. Its primary function is to intelligently guess the character encoding of a given text file or data streamed via standard input.

This tool is invaluable when dealing with text files that lack explicit encoding information, such as a Byte Order Mark (BOM) or other metadata. By statistically analyzing byte sequences within the file, chardet attempts to identify the most probable encoding (e.g., UTF-8, Latin-1, Shift_JIS, etc.).

The output typically includes the detected encoding name and a confidence level (a percentage), indicating the probability of the guess being correct. While highly effective for a wide range of common encodings, it's crucial to remember that encoding detection is a heuristic process, meaning it's an educated guess and not always 100% accurate, especially for short or ambiguous content.

chardet relies on heuristic analysis; therefore, its detection is an educated guess and not always definitive. Accuracy can be lower for very short files, files with limited character diversity, or content that is ambiguous between multiple encodings. It may occasionally misidentify encodings, especially for uncommon or custom character sets. While generally fast, processing extremely large files might consume significant memory or time.

The underlying chardet library originated from Mozilla's UniversalCharDet, developed as part of the Firefox web browser to handle various character encodings found on the web. The Python binding, known as python-chardet, made this robust detection capability accessible to Python developers. The chardet command-line utility is typically provided as a simple wrapper script within the python-chardet package, allowing users to leverage the library's power directly from the shell without writing Python code. Its adoption grew significantly with the increasing need to correctly interpret and process text data from diverse sources and locales, becoming a standard tool for character encoding identification.

file(1), iconv(1), enca(1)