How does CSV XLSX conversion work?
Files are parsed and written in your browser using SheetJS. No files are uploaded.
Browser-local tool
CSV XLSX Converter
Convert CSV to XLSX or export the first XLSX sheet to CSV directly in your browser.
Conversion direction
Drag and drop files here, orbrowse
Selected spreadsheet
Supported: CSV or XLSX, one file at a time, up to 20 MB. XLSX to CSV uses the first sheet only.
No spreadsheet selected
0 B
CSV and XLSX files are parsed and written in this browser tab with SheetJS. Files are not uploaded to a server.
Frequently asked questions
Can I convert XLSX back to CSV?
Yes, the first sheet of any XLSX workbook can be exported to CSV.
Are formulas preserved?
Formula cells are detected and disclosed but not evaluated. The output contains the last computed values.