Davemi ToolsSpreadsheet Converter
Convert between CSV, Excel, OpenDocument, and Apple Numbers files — right in your browser.
Drop a spreadsheet here or browse
CSV, XLSX, XLS, ODS, or Apple Numbers
Supported formats
Upload CSV, Excel (.xlsx, .xls, .xlsb), OpenDocument (.ods, .fods), or Apple Numbers (.numbers) files. Convert to Excel, CSV, or OpenDocument format — all processed locally, nothing uploaded.
How it works
- Drop or select your spreadsheet file.
- Preview the data and check the detected sheets.
- Choose your target format.
- Click Convert & Download.
Frequently Asked Questions
Which formats can I upload?
CSV, Excel (.xlsx, .xls, .xlsb), OpenDocument Spreadsheet (.ods, .fods), and Apple Numbers (.numbers) files.
Why can't I convert to Apple Numbers format?
Numbers is a closed, undocumented Apple format. Reading .numbers files works reliably, but the best available open-source writer only exports a small range from the first sheet — not a full, reliable conversion. Rather than risk silently losing your data, we only offer Numbers as an input, not an output.
What happens to multiple sheets when converting to CSV?
CSV can only hold one sheet, so if your file has more than one, you'll be asked to pick which sheet to export. Converting to XLSX, XLS, or ODS keeps every sheet.
Is my spreadsheet uploaded anywhere?
No. Reading, converting, and generating the output file all happen locally in your browser — nothing is sent to a server.
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