Choose a direction
Select XLSX to CSV or CSV to XLSX, then choose a file from your device.
XLSX to CSV.
CSV to XLSX.
Convert spreadsheet files without creating an account. Your data stays in your browser, and the original file is never changed.
Free for everyone No file upload No added email-row cap
Choose an XLSX workbook
Drop a .xlsx file here or choose from your device
Up to 50 MB · No sign-up · Excel limits and available device memory applyYour file stays on your device. The conversion runs in your browser. Refresh List does not receive or store the file. Close this tab or use “Clear file” to remove the working copy.
Keep the right things intact. CSV can hold the values from one worksheet, not the full Excel workbook structure. We show that boundary before download and preserve CSV fields as text by default when making an XLSX file.
HOW TO CONVERTThree steps.
Three steps.
Your file stays local.
Review the options
Pick the worksheet, separator, and safe value handling that fit your file.
Convert and download
We create the converted file in your browser. Your original stays unchanged.
FORMAT LIMITS, EXPLAINEDChoose CSV when you need
Choose CSV when you need
the values, not the workbook.
CSV is useful for transferring one table between tools. It is not an Excel workbook format.
XLSX to CSV
Choose a worksheet. The exported CSV contains its saved cell values. Formulas become their last saved results. Formatting, multiple worksheets, comments, charts, and validation are not included.
CSV to XLSX
CSV fields become cell values in a new workbook. Text is preserved by default, including leading zeros and formula-looking strings. Optional number detection converts only clear, short numbers.
50 MB file sizeMaximum input size. There is no added email-row cap, but Excel’s worksheet limits and your browser’s available memory still apply. Larger CSVs are split across worksheets when needed; unsupported or oversized ranges are declined without partial output.
COMMON QUESTIONSWhat conversion can
What conversion can
and cannot keep.
Are my files uploaded?+
No. The converter reads and converts files in your browser. The file is not sent to Refresh List or stored on our servers.
Can CSV preserve every part of an Excel workbook?+
No. CSV is a plain-text format for one worksheet. It cannot retain formatting, formulas, comments, charts, validation, or other worksheets. This tool lets you choose a worksheet and exports its saved cell values.
Will converting CSV to XLSX change my IDs or leading zeros?+
By default, all CSV values are stored as text in Excel. This protects identifiers, long numeric strings, and leading zeros. You can optionally convert unambiguous numbers to numeric cells.
How large a file can I convert?+
The browser converter accepts files up to 50 MB. Large files need more memory, and the available memory depends on your device and browser. Very large cell ranges may be declined safely rather than partially converted.
What happens if a CSV has more rows than one Excel worksheet allows?+
The converter continues the rows in additional worksheets in their original order. It does not discard rows to fit one worksheet.