File & internet
XLSX to CSV
Convert the first worksheet in an Excel workbook into CSV locally. Nothing you enter leaves your browser.
The selected file is processed only in this browser. No upload is made.
Your result will appear here.
What this tool does
About the XLSX to CSV
This converter reads XLSX input and rewrites the same usable information as CSV. It changes the representation, not the meaning of the source data, except where the target format cannot express the same structure.
It is designed for quick file and network calculations without sending the selected file to an application server.
How to use it
- Choose the source file in the workbench.
- Review any output settings shown beside the file control. Then select “Convert to CSV.”
- Inspect the result and download the new file. Keep the original until you have verified the converted copy.
Practical example
Start with a known input
Try this sample input: Use the pre-filled sample values in the workbench. Select “Convert to CSV” and compare the result with the source before using it elsewhere.
What to know about the result
- CSV is designed for rows and columns. Nested values must be flattened or represented as text, and quoting is used when a cell contains a comma, quote, or line break.
- XLSX is a workbook format. These tools operate on the first worksheet and use the first row as column names where a table structure is required.
- Processing happens in this browser. Your entered text and selected files are not sent to FormatCalc for conversion.
Common questions
Using the XLSX to CSV
Is the XLSX to CSV free to use?
Yes. FormatCalc's XLSX to CSV is free to use with no account required.
Is my data private when I use the XLSX to CSV?
Yes. This tool processes your input locally in your browser. FormatCalc does not upload or store what you enter.
How do I use the XLSX to CSV?
Choose or paste your file data, then choose Convert to CSV. The conversion stays on your device.
What should I check before using the result?
CSV is designed for rows and columns. Nested values must be flattened or represented as text, and quoting is used when a cell contains a comma, quote, or line break. XLSX is a workbook format. These tools operate on the first worksheet and use the first row as column names where a table structure is required. Processing happens in this browser. Your entered text and selected files are not sent to FormatCalc for conversion.