Excel to CSV
Convert every sheet of an .xlsx to CSV without Excel — dates and quotes handled.
About this tool
Drop an .xlsx; pick a sheet (or download all as a ZIP) and a delimiter; copy or download the CSV. The workbook is unpacked and read entirely in your browser.
What a faithful conversion has to get right
A .xlsx is a ZIP of XML files, and reading one properly means more than splitting cells: text lives in a shared-strings table, numbers are stored raw, dates are day-counts since 1900 that only a cell style reveals, booleans are 0/1, and formulas store their last calculated result. This tool handles each — dates come out as ISO dates rather than 45292, formulas contribute their cached values, and fields containing commas, quotes or line breaks are quoted per the CSV standard (RFC 4180) so other programs read them back correctly. The delimiter choice exists because Excel in most of Europe expects semicolons; tab output makes a TSV. Honest scope: CSV carries values only, so formatting, colours, merged cells, comments and charts are dropped by definition, and the old binary .xls format isn't supported (save as .xlsx first). The reason to do this in a browser rather than on a converter site is that spreadsheets are where the customer lists and finances live. View the result with the CSV viewer, turn it into JSON with Excel to JSON or CSV to JSON, and go back with CSV to Excel.
Frequently asked questions
Do dates come out correctly?
Yes — cells styled as dates are converted from Excel's serial numbers to ISO dates (2024-03-15), and date-times keep the time. Plain numbers stay numbers.
What happens to formulas?
Their last calculated value is exported, as Excel saved it. The formula itself isn't (CSV has no formulas).
Can I get all sheets?
Yes — 'All sheets (ZIP)' writes one CSV per sheet, named after the sheet.
Is the workbook uploaded?
No — it's unpacked and parsed in your browser. Nothing leaves your device.