Free · Private · In-Browser
XLSX to CSV Converter — Export Excel Files to CSV
Open the converterThis XLSX to CSV converter reads Excel workbooks and emits CSV files, fully in your browser. Single-sheet workbooks return a single CSV; multi-sheet workbooks return a ZIP with one CSV per sheet, named after the sheet.
CSV is the universal interchange format for tabular data. Every database, every BI tool, every script, every spreadsheet program reads CSV without complaint. XLSX is what Excel writes by default — a zipped XML package with formatting, formulas, and multi-sheet structure that most non-Excel tools cannot consume directly.
The tool uses SheetJS (the xlsx package), a widely-used library for Excel parsing. Conversion runs entirely in your browser, so workbooks containing financial data, employee records, or proprietary numbers never get uploaded to a cloud service.
Formulas are evaluated to their cached values (the same number you see in Excel). Dates come through as ISO strings. Empty cells produce empty CSV cells. Multi-sheet workbooks are bundled as a ZIP archive containing one CSV per sheet.
Frequently asked questions
Are my workbooks uploaded?
No. SheetJS runs in your browser. The XLSX and CSV files stay on your device.
How are multi-sheet workbooks handled?
You get a ZIP archive containing one CSV per sheet, each named after the sheet (e.g. Sheet1.csv, Q4-Forecast.csv).
Are formulas preserved?
Formulas are evaluated to their cached values. The CSV contains the result, not the formula expression.
What about merged cells?
Merged cells are split — the merged value is placed in the top-left cell, and the rest become empty cells.
What is the file size limit?
25MB per workbook on input. The CSV output can be larger or smaller depending on the data.
Related tools
Files stay on your device. No login. Installs as a PWA on iPhone, Android, and desktop.
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