How to Convert Excel to CSV Online for Free

Use the free QuickToolz office tools — no signup, no install, works in your browser.

Why Convert Excel to CSV?

Excel files (.xlsx) are great for complex spreadsheets with formulas, formatting, and multiple sheets, but many systems only accept plain CSV data. Databases, data import tools, email platforms, and APIs typically require CSV. Converting Excel to CSV strips out formatting and formulas while preserving the raw data values.

How to Convert Excel to CSV Online

1. Upload your Excel file (.xlsx or .xls) to the converter.
2. Select which sheet to convert if the file has multiple worksheets.
3. Click Convert to process the file.
4. Download the CSV file ready for import into any system.

What Gets Preserved vs Lost

Preserved: All cell values, text, numbers, and dates. Column headers in the first row. The basic grid structure of rows and columns.

Lost: Formulas (replaced by their calculated values), cell formatting (colors, fonts, borders), merged cells, charts and images, and data from other sheets not selected.

Handling Excel Dates

Excel stores dates as serial numbers internally. When converting to CSV, dates should be formatted as readable strings (YYYY-MM-DD or MM/DD/YYYY). QuickToolz converts Excel date serials to ISO format automatically so dates appear correctly in the output CSV.

Multiple Sheet Files

If your Excel workbook has multiple sheets, you can convert them one at a time by selecting each sheet in the tool. For bulk conversion of all sheets into separate CSV files, download each sheet individually.

Frequently Asked Questions

Does it support .xls files (older Excel format)? Yes — both .xlsx (Excel 2007+) and .xls (Excel 97-2003) are supported.

What happens to merged cells? The value appears in the top-left cell of the merged range; other cells in the merged area become empty.

Is there a file size limit? QuickToolz handles typical spreadsheet files without size restrictions in the browser.