JSON to Excel, honestly
This tool writes CSV — plain text with one row per line — not an Excel .xlsx workbook. Excel, Google Sheets, LibreOffice Calc and Numbers all open CSV directly, which is what most people searching for a way to convert JSON to Excel need. What CSV cannot hold is anything beyond values: there is one sheet, no formatting, no column widths and no formulas. Save it as .xlsx from Excel if you need those.
The download starts with a UTF-8 byte-order mark (BOM). Without it, Excel on Windows reads a CSV file in the local code page and accented letters turn into pairs of odd characters — Zoë becomes Zoë. Copying the text leaves the mark out, since a pasted mark is just an invisible character.
How JSON becomes rows and columns
Each object in the array becomes a row. The columns are every key that appears in any object, in the order they are first seen, so objects with different keys still line up; a missing key leaves an empty cell. Nested objects are flattened with dot paths — {"address": {"city": "Leeds"}} becomes a column called address.city. Arrays stay whole and are written as JSON inside one cell, because there is no single right way to spread a list across columns. null becomes an empty cell.
Cells are quoted as RFC 4180 describes: a value containing the separator, a double quote or a line break is wrapped in double quotes, and quotes inside it are doubled. Rows end with CRLF.
Commas, semicolons and tabs
In countries that write decimals with a comma, Excel expects semicolon-separated files and puts a comma-separated one all in column A. Choose the semicolon separator for those, or tab for a .tsv file. Going the other way, CSV → JSON detects the separator from the first line.
Formula injection
A spreadsheet treats a cell that starts with =, +, - or @ as a formula. If the JSON came from users — names, comments, form answers — turn on “Protect against spreadsheet formulas”: text cells starting with those characters get a leading apostrophe, so the spreadsheet treats them as text instead of running them. Numbers, including negative ones, are left alone.