Excel to JSON
Convert an Excel workbook to JSON or JSON Lines. Column names become keys, dates become ISO text, and you choose the sheets and check a preview before you download or copy.
Runs locally in your browser. Your input is not uploaded or saved.
How to convert Excel to JSON
- Choose an .xlsx or .xlsm file, or try the example workbook.
- Check the preview. Choose the sheets, where column names come from and the output format.
- Download the JSON file or copy it.
How a spreadsheet becomes JSON
Each row becomes an object, and the column names become its keys. By default the names come from the first row with data, so a title above the table is skipped. You can choose another row, use column letters, or write each row as a list of values.
Empty cells become null, and completely empty rows are left out. Blank column names become Column C, and repeated names get a number, such as name (2).
One sheet gives a list of rows. Several sheets give an object with one list per sheet name. Hidden sheets are listed but not chosen at first.
Numbers, dates and formulas
Numbers, text and TRUE/FALSE keep their types, and text such as 007 stays text. Numbers are read as Excel stores them, with up to 15 significant digits, so formatting such as currency signs or percentages is not added.
Dates become ISO text such as 2026-10-24, or 2026-10-24T10:15:00 when the cell shows a time. Times become 10:15:00, and durations such as 36:00:00 keep their full hours. Excel stores no time zone, so none is added.
Formulas give the result saved in the file. Errors such as #N/A are kept as text. A formula saved without a result, which some apps do, becomes null; opening and saving the file in Excel calculates it.
Merged cells and nested keys
Merged cells fill their whole area by default, so a region merged down several rows appears in each of those rows. Columns named like address.city can become nested objects, which reverses what JSON to Excel does.
Limits
Files up to 50 MiB and 10,000,000 filled cells. Old .xls, .xlsb and .ods files are not supported; save them as .xlsx first. For CSV files, use the Data Converter.
Where does my data go?
Conversion runs in your browser. Your workbook is not uploaded or saved by this tool. The site may record a basic tool view or a successful download or copy, never your data.
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