CSV to XLSX Converter
Convert CSV (Comma-Separated Values) data into Microsoft Excel XLSX format with professional formatting, styling, and Excel-specific features
Excel Options
Recommended Settings
Pro Tips
- •XLSX files open natively in Microsoft Excel, Google Sheets, and LibreOffice Calc
- •Auto-sized columns ensure all data is visible without manual adjustment
- •Frozen headers stay visible when scrolling through large datasets
- •Header styling makes data tables more professional and readable
Most Popular
Most users enable all options for professional, Excel-ready spreadsheets
When to Use This Tool
Convert CSV data exports into professional Excel spreadsheets for business reports, financial analysis, and executive dashboards. XLSX format preserves formatting, supports formulas, and is the standard for corporate reporting.
Transform CSV datasets into Excel files for sharing with colleagues, clients, or stakeholders who prefer Excel format. XLSX files are universally recognized and open in all major spreadsheet applications.
Prepare CSV data for advanced Excel features like pivot tables, charts, conditional formatting, and formulas. XLSX format enables all Excel functionality that isn't available in plain CSV files.
Convert database query results from CSV to Excel format for easy analysis, filtering, and visualization. Add professional formatting to make raw data more accessible and presentable to non-technical users.
How It Works
Parse CSV input, handling quoted values and special characters
Convert CSV rows into Excel worksheet data structure
Calculate optimal column widths based on content length
Apply header row freeze pane if enabled (stays visible when scrolling)
Style header row with bold text and blue background if enabled
Generate native Excel XLSX file using SheetJS library
Trigger automatic download of the Excel file
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Files never leave your device. All processing happens locally in your browser.
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Secure
No data collection, no tracking, no sign-up required.
Frequently Asked Questions
What's the difference between CSV and XLSX?
CSV is a simple text format that stores data as comma-separated values. XLSX is Excel's native binary format that supports formatting, formulas, multiple sheets, cell styling, charts, and advanced features. XLSX files are larger but much more powerful than CSV.
Will the XLSX file open in Excel?
Yes! The tool generates native Excel 2007+ XLSX files that open perfectly in Microsoft Excel, Google Sheets, LibreOffice Calc, and all major spreadsheet applications. All formatting and features are preserved.
What does 'freeze header row' do?
Freezing the header row is an Excel feature that keeps the first row visible when you scroll down through large datasets. This makes it easy to see column names no matter where you are in the spreadsheet - very useful for long data tables.
How does auto-size column width work?
The tool measures the length of content in each column and sets the width accordingly, ensuring all data is visible without truncation. Column widths are capped at 50 characters to prevent excessively wide columns from single long values.
Can I add multiple sheets to the Excel file?
This tool creates a single-sheet Excel file. If you need multiple sheets, you can open the generated file in Excel and add more sheets manually, or convert multiple CSV files separately and combine them in Excel.
Does this preserve data types like numbers and dates?
Excel will automatically detect and format numbers, dates, and other data types when you open the file. The tool preserves all data as text during conversion, and Excel's auto-detection handles type conversion intelligently.