CSV to XLSX Converter

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Options

If unchecked, the first row will be treated as data.

If checked, values like "123" or "true" will be saved as numbers/booleans. If unchecked, all data will be saved as text.

About this Tool

Easily convert your CSV data into a downloadable Excel spreadsheet (.xlsx format). This tool processes the data in your browser and generates a file for you to save, solving the need for offline tools or servers for quick conversions.

How does it work? Uses libraries like SheetJS to parse CSV and create an XLSX binary, then triggers download.

  1. Paste your CSV data into the text area.
  2. Click the "Download .xlsx" button.
  3. Your browser will prompt you to save the generated Excel file.
  • Sharing CSV data with non-tech users via Excel.
  • Importing logs to spreadsheets for analysis.
  • Batch converting reports.
  • Direct conversion to modern Excel .xlsx format.
  • Completely client-side, no data is uploaded.
  • Handles headers and data rows correctly.

XLSX is XML-based format by Microsoft. Conversion involves mapping CSV rows to sheet cells, preserving data types where possible.

Does it support formulas?

No, plain data only.

Large datasets?

Depends on browser; small to medium best.

Encoding?

UTF-8.

All calculations and data processing for this tool are performed locally in your browser. We do not send any of your data to our servers, ensuring your information remains private and secure.