Filewisp

Fix CSV Encoding

Read CSV files encoded as Shift-JIS, UTF-16, or UTF-8 and save them as Excel-friendly UTF-8 CSV with BOM. Everything runs in your browser.

Checks before and after data conversion

1Before converting

  • Keep the source file and confirm its encoding and data format.
  • Check whether the first row contains headers and whether field names look correct.
  • For personal or sensitive data, confirm where processing happens and who will receive the output.

2After converting

  • Use the preview to verify text, column names, and row counts.
  • Open the result in Excel or the destination system and check dates and long numbers.
  • Save the converted file under a new name so it can be compared with the source.

Common next steps

What is Fix CSV Encoding?

Use this when a Japanese CSV opens as garbled text in Excel or another spreadsheet app. The tool decodes the source file and exports a clean UTF-8 CSV with BOM, which Excel handles more reliably.

Convert CSV for Excel

Decode Japanese Shift-JIS CSV or UTF-16 CSV and save it as UTF-8 with BOM, a format Excel usually opens more reliably.

Garbled characters usually mean the CSV source encoding does not match the encoding expected by Excel. Select the original encoding, then export a clean UTF-8 CSV.

Supported encodings

  • Shift-JIS CSV from Japanese Windows and Excel workflows
  • UTF-8 and UTF-8 CSV with BOM
  • UTF-16 LE and UTF-16 BE
  • UTF-8 output with or without BOM

Choosing the output encoding

UTF-8 with BOM
Best when the CSV will be opened directly in Excel, especially with Japanese text.
UTF-8 without BOM
Best for web services, APIs, scripts, and developer tools.

How to use

  1. 1Upload a CSV file
  2. 2Choose the source encoding
  3. 3Choose the output format
  4. 4Download the fixed CSV

FAQ

Can it read Shift-JIS?

Yes. Choose Shift-JIS as the source encoding, then export as UTF-8 with BOM.

Is my file uploaded?

No. The conversion runs locally in your browser.

Why export UTF-8 with BOM?

The BOM helps Excel recognize the file as UTF-8, which reduces garbled Japanese text.

Related tools

Need help choosing the right workflow?

The guide section covers format differences, compression tips, and common PDF workflows.

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