Convert CSV to Excel instantly

Convert CSV files to Excel XLSX in your browser. No upload needed. Your data stays on your device. Free and instant.

Drop your CSV file here

or click to browse

Your files stay private
No server upload
Instant conversion

Example

Input (CSV)

name,revenue,quarter
Widget A,12500,Q1
Widget B,8900,Q2

Output (XLSX)

[data.xlsx]
Excel spreadsheet with 1 sheet
File size: 8 KB

About this converter

CSV files work everywhere but look plain. When you need to share data with someone who expects a proper Excel file, or you want column widths, sheet names, and the ability to add formatting later, XLSX is the right format. This converter uses SheetJS to build an Excel workbook from your CSV data, entirely in the browser. Your data is not uploaded to any server. The output is a standard .xlsx file that opens in Excel, Google Sheets, LibreOffice, and Numbers.

CSV vs XLSX

Comma-Separated Values (CSV)

CSV (Comma-Separated Values) is a plain-text format for storing tabular data where each line represents a row and values are separated by commas.

Common uses: spreadsheets, databases, and tabular data

RFC 4180 (CSV specification)

Microsoft Excel Spreadsheet (XLSX)

XLSX is the default spreadsheet format for Microsoft Excel (2007 and later). It stores data, formulas, charts, and formatting in a compressed XML-based container.

Common uses: spreadsheets, financial reports, data analysis, and business reporting

How to convert CSV to XLSX

  1. 1

    Upload

    Upload your CSV file using the drop zone above, or click to browse your device.

  2. 2

    Convert

    Click the "Convert to XLSX" button. The conversion runs instantly in your browser.

  3. 3

    Download

    Download your converted XLSX file. No data was sent to any server.

Frequently Asked Questions

Last updated: 2026-03-23