Convert between CSV and Excel instantly. No uploads—100% private.
Drag & drop CSV or XLSX files here
or
🔒 Your files stay on your device. Nothing is uploaded to any server.
Our CSV to XLSX Converter allows you to effortlessly switch between CSV and Excel formats. Whether you're dealing with raw data exports or structured spreadsheets, this tool provides a fast, reliable, and completely private solution.
Convert CSV to Excel (XLSX) or Excel to CSV with equal ease and accuracy.
All processing happens in your browser. Your sensitive data never touches any server.
Upload multiple files at once and convert them all simultaneously for maximum efficiency.
Drag and drop your CSV or XLSX files into the secure drop zone.
The tool automatically detects the file type and prepares the conversion.
Conversion starts immediately. No waiting for server response.
Download your newly converted files individually or as a complete ZIP archive.
Yes, 100%. All processing happens locally in your browser. Your spreadsheets and their data are never uploaded to any server, keeping your financial and business data completely private.
Yes, you can upload multiple CSV files and convert them all to XLSX at once, or vice versa. The results can be downloaded individually or as a ZIP file.
Since the tool runs in your browser, it is limited by your computer's memory. Most standard spreadsheets will work perfectly, but extremely large files (above 100MB) might slow down the conversion.
When converting from XLSX to CSV, only the raw data is preserved as CSV is a plain-text format. When converting from CSV to XLSX, we create a clean, modern Excel file with your data.
Your data never leaves your browser. All processing is done locally on your machine, ensuring maximum security and speed. No server calls, no tracking, no risk.
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Crafted with care by sidme