How do I convert a CSV file to Excel without Office?

Drop your CSV onto AllConvert, select XLSX as the output format, and click Convert. You get a standard Excel workbook without needing Microsoft Office installed — everything runs in your browser.

Will my data change during the CSV to XLSX conversion?

No. Every row and value from the CSV is written into the spreadsheet as-is, with quoted fields and embedded commas handled correctly.

Is my data uploaded to a server?

No. The conversion runs entirely in your browser using JavaScript — your data never leaves your device, which makes it safe for sensitive spreadsheets.

Convert CSV to Excel (XLSX) Online Free

Got a CSV export you need as a proper Excel file? AllConvert converts CSV to XLSX instantly, right in your browser. No upload, no account, no Microsoft Office required.

Try It Now — Convert CSV to XLSX

Why convert CSV to XLSX?

CSV is great for moving data between systems, but it is just raw text: no formatting, no multiple sheets, no charts, and Excel sometimes mangles it on open — splitting columns wrong, breaking dates or stripping leading zeros from phone numbers and postal codes. Converting to a real XLSX workbook gives you a file that opens cleanly in Excel, Google Sheets and LibreOffice every time, ready for formatting, formulas and charts.

What happens during the conversion?

AllConvert parses your CSV — handling quoted fields, commas inside values and line breaks correctly — and writes each row into a proper spreadsheet grid in a new XLSX workbook. The result is a standard Excel file with your data in the first sheet, one cell per value.

Round-tripping your data

Need to go the other way later? AllConvert also converts XLSX back to CSV and XLSX to JSON, so you can move freely between spreadsheet and data formats without installing anything.

How to convert

Open AllConvert and drop your CSV file onto the page.
Select XLSX from the format dropdown on the file card.
Click Convert and download your result.

The entire process runs locally in your browser. Nothing is uploaded, and it works on desktop and mobile, in Chrome, Firefox, Safari, and Edge.

Convert CSV to XLSX Now