Tools / File Converter / CSV to XLSB Converter

CSV to XLSB Converter

Convert CSV files to XLSB. Free and without uploading.

This tool converts CSV files to XLSB. CSV stores table data as plain text: one record per line, values separated by commas or semicolons. It carries no formatting or multiple sheets.

Binary Excel workbook. The tool detects the delimiter (comma, semicolon, tab) and decimal style by itself, so numbers arrive in Excel as numbers.

Conversion happens inside your browser; your files are never sent to a server.

How to use

1. Drag and drop your CSV files, paste them, fetch one from a link, or use "Choose files".
2. The target format is preselected; you can add several files at once.
3. Press "Convert" and download the XLSB files.

Frequently asked questions

Is anything lost when converting CSV to XLSB?

The content is kept; formatting the target format doesn’t support (such as colours or fonts) may be lost.

How many files can I convert at once?

There is no limit. Download the results one by one or as a ZIP.

Are my files uploaded?

No. Your CSV files are converted to XLSB inside your browser.