Skip to content
GRID16

Convert Excel to JSON

This tool converts an Excel workbook (.xlsx) to JSON in your browser. Every sheet with values becomes its own JSON file, numbered by its position in the workbook. A number cell becomes a JSON number, a boolean becomes true or false, a date becomes an ISO date, and an empty cell or a formula error becomes null; text always stays a string, even a value that looks like a number. With the header row on, the first row names the fields and every later row becomes an object; turn it off and every row becomes an array of values instead. Your file is never uploaded.

Runs in your browser

Drop a file here

XLSX, up to 50 MB

How it works

  1. 1 Choose an Excel (.xlsx) file.
  2. 2 Say whether the first row is a header row.
  3. 3 GRID16 reads every sheet in your browser.
  4. 4 Download one JSON file per sheet that has values.

Questions

What happens with a workbook that has several sheets?
Every sheet that holds at least one value becomes its own JSON file, numbered by its position in the workbook. An empty sheet, which old Excel defaults often leave behind, is skipped.
What does the header setting change?
With a header row the first line names the fields and you get a list of objects. An empty header cell is named by its column letter, and a name that repeats gets its column letter added, so no column is ever dropped. Without a header you get a list of rows instead.
How do numbers, dates and text come out?
A number becomes a JSON number with its exact stored value, a boolean becomes true or false, and a date becomes an ISO date such as 2026-09-14, or 2026-09-14 13:45:00 when it carries a time. Text always stays a string, so a value like "00123" is not turned into a number.
What does an empty cell or a broken formula give?
The JSON value null. A formula that errored has no cached value to fall back on, so it comes out the same way an empty cell does.
Does it read the older .xls format?
No. Only the newer .xlsx format is read; a legacy .xls file is not recognized.
Is my file uploaded to a server?
No. The conversion happens in your browser; the file never leaves your device.

More tools