Excel (.xlsx) to CSV Converter
Convert an Excel workbook to CSV without uploading it: pick the sheet, and dates, numbers and text come out exactly as stored — read directly from the .xlsx file in your browser.
Excel (.xlsx) to CSV Converter
Runs in your browser — nothing you enter is uploaded or stored.
Scratchpad auto-saved
How it works — in four simple steps
No signup and nothing to install — it all runs in your browser.
Open your workbook
Drop an .xlsx file on the box or click to choose one; pick the sheet if the workbook has several.
Set the options
Adjust the options above the boxes — the output updates instantly as you change them.
Check the result
Read the status line: it reports rows, keys and any value that couldn't be represented in CSV.
Copy or download
Copy the CSV or download it as a .csv file. Nothing was uploaded at any point.
Seeing 0.12 instead of 12%? CSV carries the stored value — percentages, currency and separators are only formatting.
Features
Header row or not
Use the first row as field names, or treat every row as data with generated column1, column2… names.
Any output delimiter
Comma for most tools, semicolon for European Excel, tab or pipe when your data is full of commas.
Opens cleanly in Excel
Add a UTF-8 byte-order mark so Excel on Windows shows accents, ₹, € and emoji correctly instead of mojibake.
Quoting control
Quote only the fields that need it (RFC 4180 minimal) or every field for strict importers.
Private by design
Parsing and conversion run in your browser with JavaScript — your data is never uploaded, logged or stored.
About the Excel (.xlsx) to CSV Converter
An .xlsx file is a ZIP archive of XML documents defined by the Office Open XML standard (ECMA-376): one XML file per sheet, a shared table of strings, and a stylesheet that says which cells are dates. This tool opens that archive with your browser's built-in decompression, reads the sheet XML, looks up shared strings, and uses the cell styles to recognise dates — so you get CSV without Excel installed and without sending the file anywhere.
Excel stores dates as serial numbers (days since 1899-12-30, or since 1904 for workbooks using the old Mac date system). Cells formatted as dates are converted to ISO dates like 2026-10-21, or date-times like 2026-10-21T14:30:00, which every system can read regardless of regional settings. Numbers are rounded to Excel's 15 significant digits, so a formula result stored as 0.30000000000000004 reads 0.3. For formulas, the last calculated value saved in the file is used.
Choose the sheet from the drop-down when a workbook has several, then pick the delimiter. Tick UTF-8 BOM if the CSV will be opened in Excel again, so non-English characters display correctly.
Examples
The Sample button builds a two-sheet workbook in your browser; this is the first sheet converted to CSV.
| # | id | name | city | score | active | joined | |
|---|---|---|---|---|---|---|---|
| 1 | 1 | Ada Lovelace | ada@example.com | London | 98.5 | true | 2024-03-14 |
| 2 | 2 | Alan Turing | alan@example.com | Manchester | 91 | false | 2023-11-02 |
| 3 | 3 | Grace Hopper | grace@example.com | New York | 95.25 | true | 2025-01-20 |
| 4 | 4 | Katherine Johnson | kj@example.com | Hampton, VA | 99 | true | 2022-07-09 |
id,name,email,city,score,active,joined
1,Ada Lovelace,ada@example.com,London,98.5,true,2024-03-14
2,Alan Turing,alan@example.com,Manchester,91,false,2023-11-02
3,Grace Hopper,grace@example.com,New York,95.25,true,2025-01-20
4,Katherine Johnson,kj@example.com,"Hampton, VA",99,true,2022-07-09This output was produced by the converter on this page with the default options — load it with the “Sample workbook” preset above and change any option to see the effect.
How Excel (.xlsx) maps to CSV
| In Excel (.xlsx) | Becomes in CSV |
|---|---|
| Text cell | the text, quoted if it contains , " or a line break |
Number 1234.5 | 1234.5 (no thousands separators) |
| Date cell (serial 46316) | 2026-10-21 |
Formula =SUM(B2:B9) | its last calculated value |
| TRUE / FALSE | true / false |
Error #DIV/0! | #DIV/0! |
| Merged cell | value in the top-left cell, others empty |
| Empty row inside the data | a row of empty fields, so row positions match the sheet |
Things that trip people up
- Old .xls files. The binary Excel 97–2003 format (.xls) isn't a ZIP of XML and can't be read here. Open it in Excel, Google Sheets or LibreOffice and save as .xlsx first.
- Displayed vs stored values. CSV gets the stored value: a cell showing 12% is 0.12, and a number shown as ₹1,200.00 is 1200. Currency symbols and thousands separators are formatting, not data.
- Formulas never recalculated. If the workbook was saved by a tool that doesn't compute formulas, cells may have no cached value and come out empty. Open and save it in Excel first.
- Password-protected files. Encrypted workbooks can't be read without the password; remove protection in Excel first.
Excel (.xlsx) vs CSV at a glance
| Property | Excel (.xlsx) | CSV |
|---|---|---|
| Specification | ECMA-376 / ISO/IEC 29500 (Office Open XML) | RFC 4180 (2005) |
| File extension | .xlsx | .csv |
| Media type | application/vnd.openxmlformats-officedocument.spreadsheetml.sheet | text/csv |
| Data types | number, text, boolean, date (as a serial number), formula | text only — every cell is a string |
| Comments | Cell notes | No |
| Nesting | None (grid; several sheets) | None (flat rows) |
- Excel (.xlsx): A sheet holds at most 1,048,576 rows × 16,384 columns (A to XFD), a cell at most 32,767 characters, and numbers keep 15 significant digits.
- CSV: Fields containing a comma, a double quote or a line break must be wrapped in double quotes, and a quote inside is written twice ("").