Free online Excel (OOXML) to OpenDocument Sheet converter. Files are processed locally in your browser — no uploads, 100% private.
Drop your .XLSX file here
or click to browse from your device
100% browser-based — no server uploads, no cloud processing
Free forever — no account or subscription required
Supports batch conversion for multiple files at once
Works on any device — desktop, tablet, and mobile
Results available in seconds — no server queue or wait time
Files are cleared immediately after processing for maximum privacy
Microsoft Excel Open XML — current default format
LibreOffice / OpenOffice Calc spreadsheet
Source: Microsoft Excel Open XML — current default format
Output: LibreOffice / OpenOffice Calc spreadsheet
100% browser-based processing — files never leave your device
Free with no file limits, watermarks, or registration required
May require specific software to open or edit
Not universally compatible with all applications
Alternative formats may offer better compression or quality
Business data analysis and financial reporting
Inventory management and scheduling
Database export/import and data migration
Scientific and statistical data storage
Keep original files before converting for maximum flexibility
Test converted output before using in production workflows
Use batch processing for multiple files to save time
Match the output format to your delivery platform for best results
Drag & drop your file or click to browse
Files are processed instantly in your browser
Save your converted or processed file
Upload your XLSX file using the drop zone above. Your file is instantly converted to ODS format right in your browser — no server upload, no waiting.
Completely. Our converter processes your XLSX file 100% in your browser using client-side code. It never leaves your device or touches any external server.
It depends on the formats. Converting from lossless to lossy (e.g. PNG to JPEG) may reduce quality. Converting lossless-to-lossless (e.g. PNG to WebP lossless) preserves all quality.
Free, instant, and 100% private. Your files are processed locally in your browser.