Excel to CSV
Save every sheet of an Excel workbook as its own CSV file. Nothing is uploaded.
Drop XLSX files here
Converted on your device. Files are never uploaded.
Up to 20 files at a time.
CSV is the plain format that databases, accounting tools and scripts import most readily. FormatJet opens your XLSX workbook with its own reader and writes each sheet to a CSV file, keeping the values and the results of formulas. Everything happens in your browser, so the spreadsheet never leaves your device.
About the formats
XLSXExcel workbook
XLSX is the workbook format of Microsoft Excel since 2007: sheets of cells with formulas, formatting and charts.
CSVCSV file
CSV stores a table as plain text, one row per line with commas between the values. Spreadsheets, databases and almost every data tool can read and write it.
Converted with Data converters (Papa Parse, yaml, fast-xml-parser), Data converters on Workers.
Questions
What happens to a workbook with several sheets?
Each sheet becomes a separate CSV named after the sheet. Download them one at a time, or all together as a ZIP with “Download all”.
Are formulas kept?
No, a CSV holds values only. Each formula cell comes out as the result Excel last saved, so recalculate and save the workbook first if it’s out of date.
How are dates written?
As ISO dates such as 2024-01-01, with the time added when the cell has one, so every program reads them the same way whatever its regional settings.
Can I convert old .xls files or protected workbooks?
No. FormatJet reads XLSX files from Excel 2007 onwards, not the older .xls format, and refuses workbooks protected with a password. Open an .xls in Excel and save it as .xlsx first.
What gets left out of the CSV?
Formatting, merged cells, charts and images. A CSV is plain text with one value per cell, so only the cell values make it across.
Excel to CSV with the API
The conversion API opens later this year.
curl https://api.formatjet.com/v1/convert?to=csv \
-H "Authorization: Bearer fj_test_…" \
-F file=@input.xlsx -o output.csv