Convert Excel to CSV online
Turn XLSX, XLS, XLSM and ODS sheets into CSV with a sheet picker, delimiter choice, date formatting and a ZIP of every sheet at once.
- Runs in your browser
- Files are never uploaded
- Free, no account
How to convert Excel to CSV
- Drop the workbook onto the page —
.xlsx,.xls,.xlsm,.xlsband.odsall work. - Choose the worksheet. Every sheet in the file is listed; the preview shows the first twelve rows so you can confirm you picked the right one.
- Set the delimiter and date format. Comma for most systems, semicolon for European Excel, tab for a TSV.
- Download. Save the current sheet as one CSV, or take every sheet at once as a ZIP with one file per worksheet.
What survives the conversion — and what cannot
CSV is a plain grid of text. That is its strength and its limitation. Knowing what will be gone before you send the file to a colleague saves an awkward round trip.
| Workbook feature | In the CSV |
|---|---|
| Cell values and text | Kept |
| Formulas | Replaced by their last calculated result |
| Number formats (currency, percent) | Your choice — raw value or the displayed text |
| Dates | Kept, in the format you select |
| Merged cells | Value in the top-left cell; the rest empty |
| Multiple worksheets | One CSV each — download them together as a ZIP |
| Colours, fonts, borders, column widths | Not representable in CSV |
| Charts, images, pivot tables, macros | Not representable in CSV |
Raw values versus displayed text
A cell showing £1,234.50 holds the number 1234.5 with a currency format
applied. Which one belongs in your CSV depends on where it is going:
- Use underlying numbers (the default) when a database, script or BI tool will read the file. You get
1234.5— parseable everywhere, no symbols or thousands separators to strip. - Turn it off when a person will read the file, or when you need to reproduce a report exactly as it looked on screen. You get
£1,234.50.
Getting dates right
Excel stores a date as the number of days since 30 December 1899, and the format decides how it looks.
Exporting “as displayed” preserves what you saw, but 03/04/2026 is ambiguous — the third of
April in London and the fourth of March in New York. If the CSV feeds anything automated, choose ISO
8601 (2026-08-16): it sorts correctly as text, has no locale ambiguity, and every database
accepts it.
Why the browser is the right place for this
Spreadsheets are where organisations keep salary bands, patient lists and unreleased financials. Uploading one to a conversion site means handing a copy to a third party, and most of those sites keep the file for hours. Here the workbook is decoded by SheetJS running in your tab; no request carries the data, so there is no copy to delete. Large files are limited only by your machine’s memory, and the tool keeps working with the network disabled.
Related conversions
Need structured output instead of a grid? Excel to JSON keeps types and nesting. Going the other way, CSV to Excel writes a real workbook with auto-fitted columns.
Questions
Is my spreadsheet uploaded to a server?
No. The workbook is decoded by WebAssembly and JavaScript inside this tab. Nothing is transmitted, which is why the tool works on confidential financial and HR data.
Can I export every worksheet at once?
Yes. “Download every sheet as a ZIP” writes one CSV per worksheet, numbered in workbook order so the sheet sequence is preserved.
What happens to formulas?
The calculated result is exported, not the formula, which is what nearly every importer expects. Charts, images and conditional formatting are not part of CSV and are dropped.
How are dates handled?
By default each date keeps the format shown in Excel. You can also force ISO 8601 (2026-08-16), day/month/year or month/day/year for a predictable import.
My file is password-protected — can it be converted?
No. Encrypted workbooks cannot be opened without the password. Remove protection in Excel with “Save as → Tools → General Options”, then convert the unprotected copy.