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CONVERT · IN YOUR BROWSER

Convert CSV, JSON and Excel online

Open a table, check data and download another format. Files stay on this device.

Up to 10 MB, 10,000 rows, 200 columns and 200,000 cells. CSV/JSON must use UTF-8. Legacy Excel (.xls) is unsupported.

Changing this rereads the CSV.

Open a file to start.

Converts selected worksheet data without preserving styles, macros or formulas. Formulas use saved results; Excel dates become ISO text. CSV text stays text, keeping leading zeros. JSON accepts object lists with simple values or row lists; empty cells may become null or empty text depending on format. Numbers over 15 digits must be JSON strings. ExcelJS (MIT).

How to use: Convert CSV, JSON and Excel online

Open a file or enter data in the tool. Choose a worksheet when there are several, check headings and values in the preview and select an output format. Download the result and verify it in the destination program.

Before you start

These formats represent data differently. Formulas, styles and multiple worksheets do not have direct equivalents in CSV or JSON. Check dates, leading zeros and delimiters.

Frequently asked questions

Does CSV preserve Excel formulas and formatting?

No. CSV stores tabular data as text; it does not preserve styles, multiple sheets or a workbook's formula logic.

How do I avoid changes to codes and dates?

Check the preview and exported file. Spreadsheet programs may interpret leading zeros and dates automatically; import as text when necessary.