Excel to JSON
Turn the rows of an Excel workbook into JSON. Nothing is uploaded.
Drop XLSX files here
Converted on your device. Files are never uploaded.
Up to 20 files at a time.
Spreadsheets are where a lot of data starts, but web apps, seed scripts and APIs want JSON. FormatJet reads your XLSX workbook with its own code and writes each sheet’s rows as JSON objects keyed by the header row. The conversion runs in your browser, and the workbook stays on your device.
About the formats
XLSXExcel workbook
XLSX is the workbook format of Microsoft Excel since 2007: sheets of cells with formulas, formatting and charts.
JSONJSON file
JSON is the text format web APIs and apps use to exchange data: objects, lists, text, numbers and true or false values, nested as deep as needed.
Converted with Data converters (Papa Parse, yaml, fast-xml-parser), Data converters on Workers.
Questions
How are multiple sheets put into the JSON?
A workbook with one sheet gives a list of rows. With several sheets you get an object whose keys are the sheet names, each holding that sheet’s rows.
Does each row become an object?
Yes, while “First row holds the column names” is ticked, which is the default: the header row supplies the keys. Untick it to get each row as an array of values.
What do formula and date cells turn into?
A formula cell gives the value Excel last saved for it, and a date becomes an ISO string like 2024-01-01, with the time if the cell includes one.
Are empty or repeated headers a problem?
No. An empty header cell becomes column_1, column_2 and so on, and a header used twice gets _2 on the second one, so keys never clash.
Which Excel files work?
XLSX workbooks from Excel 2007 or later, up to 50 MB. Old .xls files and password-protected workbooks can’t be read.
Excel to JSON with the API
The conversion API opens later this year.
curl https://api.formatjet.com/v1/convert?to=json \
-H "Authorization: Bearer fj_test_…" \
-F file=@input.xlsx -o output.json