📝 Text File Encoding Detector
Professional text encoding detector that analyzes uploaded text files to identify their character encoding. Features BOM detection, statistical analysis, and confidence scoring for UTF-8, UTF-16, Windows-1252, ISO-8859-1, and other common encodings. Perfect for developers handling international text data and file conversion projects.
Encoding Analysis:
example.txt → UTF-8 Encoding (95% Confidence)
1,024 bytes analyzed • BOM detected • Unicode text
🎯 Primary Encoding Detection
EF BB BF (UTF-8 BOM detected)
🔍 Alternative Possibilities
📄 Content Preview (UTF-8 Decoded)
🔬 Technical Analysis
1,024 bytes
1,024 bytes (100%)
892 characters
24 (2.3%)
💡 Recommendation:
File is correctly encoded as UTF-8. No conversion needed. This encoding supports international characters and is web-safe.
How to Use This Text File Encoding Detector
How to Use the Text File Encoding Detector
Step 1: Upload Your Text File
Click "Choose File" and select a text file from your computer. Supported formats include .txt, .csv, .log, .json, .xml, .html, .css, .js, .py, and other text-based files. The tool works best with files containing international characters or special symbols.
Step 2: Choose Sample Size
Select how much of the file to analyze. 1 KB is fast for most files, 5 KB provides balanced accuracy, 10 KB offers high accuracy for complex files, and "Full file" analyzes everything (slower for large files but most accurate).
Step 3: Enable Content Preview (Recommended)
Check "Show content preview" to see a sample of the decoded file content. This helps verify that the detected encoding produces readable text and allows you to spot encoding issues visually.
Step 4: Detect Encoding
Click "Detect Encoding" to analyze your file. The tool will identify the most likely encoding using BOM detection (for Unicode files) and statistical analysis (for other formats), providing confidence scores for each possibility.
Step 5: Review Results
Examine the primary encoding detection, alternative possibilities, content preview, and technical analysis. Use the confidence scores and preview text to verify the results and choose the correct encoding for your file.
How It Works
How the Text File Encoding Detector Works
Multi-Layer Encoding Detection Process
The Text File Encoding Detector uses a sophisticated multi-stage analysis process to identify character encodings:
- BOM Detection: First checks for Byte Order Mark signatures (UTF-8: EF BB BF, UTF-16 BE: FE FF, UTF-16 LE: FF FE, UTF-32 variants)
- File Reading: Uses JavaScript FileReader API to read the file as an ArrayBuffer for binary byte analysis
- Statistical Analysis: Analyzes byte frequency patterns, character distribution, and text structure characteristics
- Encoding Inference: Applies heuristics for common encodings (ASCII, UTF-8, ISO-8859-1, Windows-1252, etc.)
- Confidence Scoring: Calculates probability scores based on byte pattern matches and text validity
- Content Validation: Attempts to decode text samples to verify encoding accuracy
Detection Algorithm Details
The detection process combines multiple techniques for maximum accuracy:
- BOM Signature Matching: Definitive identification for Unicode files with Byte Order Marks
- Byte Range Analysis: Checks if bytes fall within valid ranges for specific encodings
- Character Frequency Analysis: Compares letter frequency against expected patterns for different languages
- UTF-8 Validation: Verifies multibyte sequence validity for UTF-8 encoding
- ASCII Compatibility: Identifies pure ASCII content that works with multiple encodings
Confidence Score Calculation
Confidence scores are calculated using weighted factors including BOM presence, byte validity, character patterns, and successful text decoding. Higher scores indicate more reliable encoding identification.
Browser-Based Security
All file analysis happens locally in your browser - no files are uploaded to servers. This ensures privacy while providing professional-grade encoding detection capabilities.
When You Might Need This
- • Software developers analyzing text files with unknown encoding from international projects and legacy systems
- • Debug character encoding issues when importing CSV files with special characters and international data
- • Data analysts processing multilingual datasets that contain mixed encoding formats from different sources
- • Web developers troubleshooting text display issues caused by incorrect encoding detection in uploaded files
- • System administrators investigating log files with encoding corruption and unreadable international characters
- • Database administrators importing text data that shows garbled characters due to encoding mismatches
- • Content managers handling multilingual website content files with various international character encodings
- • File conversion specialists identifying source encoding before converting text files to different formats
- • Quality assurance testers verifying that applications correctly handle files with different character encodings
- • Students learning about character encodings and text processing in computer science and programming courses
Frequently Asked Questions
What text encodings can the detector identify?
The detector identifies UTF-8, UTF-16 (LE/BE), UTF-32 (LE/BE), ISO-8859-1 (Latin-1), Windows-1252, ASCII, and several other common encodings. It uses BOM detection for Unicode formats and statistical analysis for non-BOM encodings, providing confidence scores for each possibility.
How accurate is the encoding detection?
Accuracy depends on file content and size. BOM-encoded files (UTF-8/16/32 with BOM) are detected with near 100% accuracy. Non-BOM files rely on statistical analysis and typically achieve 85-95% accuracy for files with sufficient non-ASCII content. Larger sample sizes improve accuracy.
Can I upload binary files or only text files?
This tool is designed specifically for text files. While it can analyze any file type, it will detect binary files and warn you that encoding detection is not meaningful for non-text data. For best results, upload .txt, .csv, .log, .xml, .html, .json, or other text-based files.
What's the difference between BOM and non-BOM detection?
BOM (Byte Order Mark) is a special signature at the beginning of Unicode files that definitively identifies the encoding. Files with BOM can be detected with certainty. Non-BOM files require statistical analysis of byte patterns, character frequency, and text structure to infer the most likely encoding.
Why does the tool show multiple encoding possibilities?
Many encodings overlap in their byte ranges, making definitive identification challenging. The tool shows confidence scores for each possibility to help you choose. For example, pure ASCII text could be valid in UTF-8, ISO-8859-1, or Windows-1252. The content preview helps verify which encoding produces readable text.