CSV to Excel
Turn CSV files into .xlsx workbooks. Drop a whole batch and convert them in one pass.
Drop CSV files here
Everything happens on your device — your files are never uploaded.
What this does
This reads each CSV's plain text and writes it into a real .xlsx workbook (Excel's Open XML format). Every row and column lands in a single sheet named Sheet1, with cells that look numeric or date-like stored as numbers and dates rather than text, so Excel treats them as values you can sum and sort.
It runs entirely in your browser, so the file never leaves your device. CSV has no styling, formulas, or multiple sheets to carry over, so the output is one plain sheet of values. The original file ordering and contents are preserved; nothing is added beyond the workbook structure Excel needs.
How it works
- 1 Drop your CSV files.
- 2 Each one becomes an .xlsx workbook.
- 3 Download each result, or grab them all as a zip.
Built with open source
- Papa Parse — Fast in-browser CSV parser. · MIT
- SheetJS (xlsx) — Reads and writes Excel spreadsheets. · Apache-2.0
Frequently asked
Does the conversion lose any data? +
No. Every row, column, and cell value is carried over as-is into the workbook. CSV holds nothing but text values, so there's nothing extra to drop.
Does it support large CSVs? +
Yes. Files are parsed and written right on your device. A very large file may take a moment and use some memory while it converts.
What about quoted fields, commas, and line breaks? +
The parser follows the CSV standard, so quoted fields with embedded commas, quotes, and newlines come through intact.
Are numbers and dates kept as text or real values? +
Cells that look like numbers or dates are written as numeric and date values, so Excel can sum and sort them. Text that just happens to contain digits stays text.
How many sheets does the output have? +
One. A CSV is a single table, so each file becomes a single sheet named Sheet1. There are no formulas, styles, or extra tabs to create.
Can I convert several files at once? +
Yes. Drop as many CSVs as you like and each one becomes its own .xlsx. Download them individually or grab them all as a zip. The only limit is your device's memory.
Are my files uploaded anywhere? +
No. Everything runs locally in your browser. The files are never sent to a server, and there's no sign-up or watermark.
Which browsers does it work in? +
Any current browser on desktop or mobile. The conversion uses standard browser APIs, so no extension or install is needed.