Choose a file to convert. It's processed locally — never uploaded. Tip: add several files to convert them all at once.
Result appears here after you select
{ } How to use
- Choose the .xlsx or .xls workbook.
- Select Process.
- Copy the JSON, or download it.
{ } How it works
Excel to JSON works on the file you upload. Select Process ▸ and it runs entirely in your browser — nothing is uploaded to a server — then shows the result in the Output panel.
Input
- Excel file — upload a file (.xlsx,.xls); it is read locally in your browser
Output
JSON — copy it, download it, or switch the Output panel to Tree view to explore it.
{ } Common uses
- Get spreadsheet data into a shape a program can consume.
- Hand a colleague’s workbook to an API that wants JSON.
- Inspect what a sheet actually contains, field by field.
{ } Limitations
- Only the first sheet is read. A workbook with several sheets loses the rest, and nothing warns you.
- The first row is treated as the header and becomes the JSON keys, so a sheet without a header row produces objects keyed by whatever happens to be in row one.
- Dates come out as Excel serial numbers rather than date strings, because that is what the cell holds. Empty cells become null, and a formula contributes its last calculated value, not the formula.
{ } FAQ
Is my data uploaded to a server?
No. Everything runs locally in your browser — your files never leave your device.
Can I process more than one file at once?
Yes — add several files and they’re all processed and downloaded together as a ZIP.
Is this tool free?
Yes — it’s completely free and needs no sign-up.
Why are my dates showing as numbers like 45678?
Because that is what Excel stores. A date cell holds a count of days from an epoch, and the format you see is separate presentation. This conversion reads the value, so you get the number. If you need it readable, add a column in the spreadsheet that formats the date as text before converting.