Tooloat

CSV to Excel converter

Open a CSV as a proper Excel file. Numbers become numbers so you can add them up, codes with leading zeros stay as text, and JSON arrays work too. Nothing is uploaded.

Tooloat runs in your browser and needs JavaScript. It opens in a moment, and your files are processed on your device.

How it works

  1. Drop your spreadsheets or CSV files.
  2. Choose the direction and output options.
  3. Download the converted files.

Why use it

  • Numbers detected.
  • Leading zeros kept.
  • JSON input.
  • Bulk.

Questions and answers

Why did Excel change my numbers?

Opening a CSV directly makes Excel guess types. A real XLSX avoids that.

Can I merge sheets?

Each file becomes a workbook with one sheet.

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