Convert XLSX to CSV, Free
Upload your XLSX file and get a CSV in seconds. No account, no watermark.
How to convert XLSX to CSV
XLSX is the modern Excel format, a ZIP archive of XML files that stores spreadsheet data along with formulas, formatting, charts, and metadata. For data exchange, analysis pipelines, and database imports, CSV is far more practical: it is plain text, universally readable, and requires no library to parse. Converting XLSX to CSV strips away everything except the raw data values, which is exactly what most data tools need.
BoltConverter converts your XLSX file on our servers. The first worksheet is extracted, each row becomes a line, and each cell value becomes a comma-separated field. Formulas are resolved to their results. After conversion, both files are deleted from the server immediately.
Upload your XLSX file
Click the upload area or drag your Excel spreadsheet onto the page.
Worksheet data is extracted as CSV
BoltConverter reads the first worksheet and converts each row and cell value into a CSV-formatted line.
Download the CSV
Click Download to save the CSV for import into databases, Python scripts, R analysis, or any data tool.
Frequently asked questions
Which worksheet is converted in a multi-sheet workbook?
The first sheet in the workbook is converted to CSV. To convert a different sheet, move it to the first position in Excel before uploading.
Are formulas included in the CSV?
No. CSV stores values only. Formulas are replaced by their last calculated values in the output. If the spreadsheet has not been recalculated, some values may be stale.
How are cells with commas in the value handled?
Values containing commas are wrapped in double quotes in the CSV output, following the RFC 4180 standard. For example, a cell value of 'Smith, John' becomes "Smith, John" in the CSV.
Is there a row limit?
There is no row limit. Files up to 100 MB are supported. Excel's own row limit is about 1 million rows.
Are my files stored on the server?
No. Both the uploaded XLSX file and the resulting CSV are deleted from our servers immediately after you download the result.