Convert XLS to CSV, Free
Upload your XLS file and get a CSV in seconds. No account, no watermark.
How to convert XLS to CSV
XLS is the legacy Microsoft Excel binary format used by Excel 97 through 2003. While Excel itself can open XLS files, many modern data tools, Python libraries, and database import tools prefer the universal CSV format over XLS. Converting your XLS file to CSV makes the data accessible to any tool that can read plain text, from shell scripts to SQL databases.
BoltConverter reads your XLS file on our servers, extracts the first worksheet, and writes the data as a comma-separated values file. Formulas are replaced by their calculated values, and formatting is discarded. After conversion, both files are deleted from the server immediately.
Upload your XLS file
Click the upload area or drag your .xls Excel file onto the page.
First sheet is extracted as CSV
BoltConverter reads the first worksheet in the XLS workbook and writes each row as a CSV line, with cells separated by commas.
Download the CSV
Click Download to save the CSV file for use in any data processing tool, database, or script.
Frequently asked questions
What is the difference between XLS and XLSX?
XLS is the legacy binary format from Excel 97-2003. XLSX is the modern XML-based format introduced in Excel 2007. Both are Excel files but use entirely different file structures. This converter handles the older XLS format.
Which worksheet is converted if the XLS has multiple sheets?
The first sheet in the workbook is converted. To convert a different sheet, open the file in Excel, move that sheet to the first position, save, and then upload.
Will formulas in the XLS be preserved as formulas in the CSV?
No. CSV stores values only. Formulas are replaced by their calculated results in the output CSV.
Is there a row or column limit?
There is no artificial row limit. Files up to 100 MB are supported.
Are my files stored on the server?
No. Both the uploaded XLS file and the resulting CSV are deleted from our servers immediately after you download the result.