CSV Encoding Fixer
Fix strange characters by decoding Windows-1252, Shift_JIS, UTF-16, or UTF-8 and downloading a compatible UTF-8 CSV.
Upload a CSV file to convert it
Your data never leaves your browser
Help, examples, limits, and privacy
How do I convert a CSV to UTF-8?
CSV files do not reliably declare their character encoding. When Excel, an accounting system, or a database opens Windows-1252 or Shift_JIS bytes as UTF-8, accents and Japanese text turn into question marks or garbled characters.
What this tool changes
- Decodes the selected source encoding and writes a new UTF-8 file.
- Can add a UTF-8 BOM for better compatibility with some versions of Excel.
- Preserves the decoded Unicode text shown in the preview.
What it leaves alone
- Rows, columns, delimiters, and cell values are not cleaned or reorganized.
- The tool does not guess replacements for text that was already permanently corrupted before upload.
- The source file remains untouched.
How it works
Why characters break. If one app saves Windows-1252 or Shift_JIS and another assumes UTF-8, the same bytes are interpreted as different characters.
Excel and UTF-8. A UTF-8 BOM can help Excel identify the file correctly without changing the actual data values.
Preserving Japanese text. Shift_JIS detection is a best guess. If the preview is wrong, choose the source encoding yourself before downloading.
Processed locally. The file stays on your device. Filenames, rows, cells, and worksheet names are never sent to us or analytics.