Convert XLSX to CSV online

Convert XLSX to CSV online in batches. Files stay in your browser and are never uploaded or stored on a server.

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Your files stay on this device and are never uploaded.

Drop files here to convert them

Up to 20 files · 50 MB each · 100 MB per batch

Choose XLSX files and convert them to CSV together in one private browser session.

How to convert XLSX to CSV

Select one or more XLSX files, start the batch, then download each CSV result or all completed files together.

This conversion reads each XLSX table and writes its rows and columns to a new CSV spreadsheet file.

Process up to 20 files per batch, with 50 MB per file and 100 MB in total.

The conversion runs locally in your browser. NDNCI never receives, stores, or sends your files to a third party.

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