Excel to CSV
Every sheet becomes its own CSV — free, in your browser
Workbooks with multiple sheets are converted one CSV per sheet, bundled into a ZIP.
100% private — Files are converted right in your browser and never uploaded to any server.
XLSX internals and sheet choice
- An xlsx is a ZIP of XML sheets — unpacked locally, cell values read straight from the shared-strings table.
- Dates arrive as serial numbers since 1900; conversion uses the workbook calendar setting.
- Formulas export as their last cached value — the stored number, not formula text.
How it works
- 1
Drop in your Excel file (.xlsx or .xls).
- 2
Choose a delimiter — comma, semicolon or tab.
- 3
Click Convert and download — a single CSV, or a ZIP if there are multiple sheets.
Spreadsheets lie until you see the raw grid
One CSV per sheet
Every sheet of a workbook becomes its own CSV file. Multi-sheet files download as a ZIP holding one CSV per sheet, each named after the sheet — single-sheet files come down directly.
Comma, semicolon or tab
Pick the delimiter your destination system expects. Choose comma, semicolon or tab from the dropdown — semicolon separates fields cleanly in German, French and other European spreadsheet exports.
Old .xls and new .xlsx
Both container formats parse: modern OOXML .xlsx and the legacy OLE2 .xls still sitting in thousands of old workbooks. The SheetJS reader identifies each by its file signature before conversion.
Frequently asked questions
What happens to multiple sheets?⌄
Each sheet becomes its own CSV file, named after the sheet, bundled into a single ZIP download.
Does it support the old .xls format?⌄
Yes — both the modern .xlsx and the legacy binary .xls format are supported.
Is my file uploaded?⌄
No — the conversion runs entirely in your browser using an on-page engine. Your spreadsheet never leaves your device.
Why choose semicolon or tab instead of comma?⌄
Some locales and tools (e.g. Excel configured for certain European regions) expect semicolon-separated values; tab-separated is handy for pasting into other apps.
Related tools
✦ What Is an Excel to CSV Converter?
An Excel to CSV converter turns a modern .xlsx workbook or a legacy .xls file into plain-text CSV that databases, shops, and data tools can import without Excel. This tool reads the file with the self-hosted SheetJS engine, converts every sheet to CSV with your chosen field separator, and names a single-sheet result after the workbook while a multi-sheet workbook produces one CSV per sheet suffixed with the sheet name. A magic-byte check tells ZIP-based OOXML apart from OLE2 containers before parsing starts, and files up to 50 MB are accepted.
How sheets become CSV files
Each worksheet is serialized row by row with cells joined by the separator you pick: comma, semicolon, or tab. Sheet names are sanitized for safe filenames, so characters forbidden by operating systems become underscores instead of breaking the download, with progress per sheet.
Delimiter choices that match your importer
- Comma for most databases, e-commerce importers, and programming libraries that expect classic CSV.
- Semicolon for European locales where the comma is the decimal mark and Excel itself exports that way.
- Tab for data full of commas, such as street addresses or product descriptions that would otherwise need heavy quoting.
What formulas and formatting leave behind
CSV stores values, not spreadsheets: formulas export as their computed values, while charts, images, pivot tables, and cell colors do not transfer at all. Date and number formatting may also look different once a plain-text importer reinterprets the text, and very large workbooks take a while because sheets convert in sequence.
Why workbooks never leave this browser tab
Parsing runs entirely on your device through an engine script loaded from this site, and the tool code contains no upload calls, no server routes, and no registration API, so workbook bytes are never posted anywhere. Only the finished CSV is built locally for download.
Pick the separator your target system expects and the import usually succeeds on the first try.
Last updated · 2026-09-01