Instantly identify the encoding of any CSV file. Everything runs in your browser — your data never leaves your device.
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Encoding analysis will appear here...Load a CSV file to analyze encoding
Three simple steps to check your CSV file encoding.
Paste your CSV data directly or upload a file. Any encoding is accepted.
The tool analyzes byte patterns, BOM markers, and character distribution to identify encoding.
See the detected encoding, confidence level, character statistics, and BOM details.
A CSV Encoding Checker is a utility that identifies the character encoding used in a CSV file. Character encoding defines how bytes are mapped to characters — choosing the wrong encoding can result in garbled text, broken special characters, or data corruption.
This tool analyzes your CSV data using multiple detection methods: BOM (Byte Order Mark) detection, byte pattern analysis, and character frequency statistics. It works entirely in your browser with no data upload, making it ideal for sensitive datasets.
Prevent data corruption
Importing a CSV with the wrong encoding produces mojibake — garbled characters that destroy your data.
Debug import errors
When a database or API rejects your CSV, encoding mismatch is often the hidden cause.
Convert between encodings
Once you know the source encoding, you can convert it to UTF-8 for universal compatibility.
Verify file integrity
Confirm the encoding before sharing CSV files with teams or importing into production systems.
The confidence score indicates how certain the tool is about the detected encoding. Higher scores mean more reliable detection.
| Confidence | Detected Encoding | What it means |
|---|---|---|
| 100% | UTF-8/16/32 (with BOM) | Byte Order Mark found — encoding is certain |
| 95% | ASCII | All characters are in 0–127 range — unambiguous |
| 90% | UTF-8 | Valid multi-byte sequences found, no errors |
| 85% | UTF-16 LE / BE | High null byte ratio detected — likely UTF-16 |
| 70% | Windows-1252 | Bytes 0x80–0x9F found (smart quotes, dashes) |
| 65% | ISO-8859-1 | High bytes present but no Windows-1252 markers |
| 50% | Ambiguous | Could be multiple encodings — manual verification recommended |
The tool uses multiple heuristics: it checks for Byte Order Marks (BOM) at the start of the file, analyzes byte patterns to distinguish UTF-8 from single-byte encodings, and examines character frequency distributions. When multiple encodings are plausible, it reports the most likely candidate with a confidence score.
A BOM is an invisible marker at the beginning of a text file that indicates the encoding and byte order. For example, UTF-8 files may start with EF BB BF, while UTF-16 LE files start with FF FE. The presence of a BOM is the most reliable encoding indicator.
ISO-8859-1 (Latin-1) and Windows-1252 are similar but not identical. ISO-8859-1 maps bytes 0x80–0x9F to control characters, while Windows-1252 maps them to printable characters like smart quotes (', ", ") and dashes (–, —). Most "Latin-1" CSV files are actually Windows-1252.
Yes. All processing happens entirely in your browser. Your file is never uploaded to any server. You can verify this by disconnecting from the internet and using the tool offline.
If your CSV was detected as a non-UTF-8 encoding, convert it to UTF-8 for maximum compatibility. Use our CSV to UTF-8 Converter tool to re-encode your file safely.
For a complete CSV workflow, explore our other free tools:
All processing happens in your browser. Your data never leaves your device.