CSV guide
Fix CSV Special Characters and UTF-8 Problems in Excel
Excel character encoding problems appear when a CSV's bytes are decoded with the wrong charset. Mojibake such as ’ or replacement diamonds is a common symptom. A CSV does not declare an Excel charset of its own, so detection is an estimate that should remain visible and overridable.
Check CSV encodingStep by step
- Open the file and review the detected encoding and confidence percentage.
- If names or punctuation look wrong, manually try UTF-8, Windows-1252, UTF-16 or Shift_JIS and reparse.
- For Excel on Windows, export UTF-8 CSV with the BOM option enabled.
- Reopen the exported file and verify a known non-ASCII value before replacing the source.
Check the result
- Check several values that contain accents, curly quotes, currency symbols or Japanese text rather than relying on an ASCII-only header.
- Confirm the encoding shown by the tool after every manual override; changing the selection reparses the original bytes.
- Open the exported file in the actual destination application because Excel, database importers and command-line tools may interpret a BOM differently.
Common pitfalls
- Windows-1252 and ISO-8859-1 are often impossible to distinguish with complete certainty.
- Shift_JIS heuristics can misclassify short files with only a few high bytes.
- A UTF-8 BOM helps Excel recognize encoding but becomes part of the byte stream for some other tools.
Try the example on this page
Choose Try sample to load this guide’s synthetic data. Adjust the settings, inspect the result and export it here. You can also choose your own file for local processing.
Open a data file to start
The parser runs off the main thread. Once loaded, you can search, sort, validate, repair and export without an account.
Original samples: international-utf8.csv
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