Skip to content
utilnook

JSON to CSV Converter

Convert JSON to CSV for Excel or Google Sheets, and CSV back to JSON. Flattens nested objects, keeps big numbers exact, and previews the table.

Runs in your browser. Nothing you enter is uploaded.

How to use

This tool converts JSON into CSV, the table format spreadsheets understand, and converts CSV back into JSON.

JSON to CSV

  1. Paste your JSON, or Open a file (a .csv file opens CSV to JSON). A list of objects works best, like [{"name": "Ada", "city": "London"}]. Each object becomes a row and each key becomes a column.
  2. Check the table preview. Missing keys leave empty cells, and the columns are every key that appears, in the order they first appear.
  3. Adjust the options if needed:
    • Flatten nested objects turns {"address": {"city": "London"}} into a column called address.city.
    • Lists are written as JSON text, or joined with semicolons.
    • Separator: Excel in many European countries expects semicolons.
    • Excel-friendly (BOM) makes Excel read accents and other non-English letters correctly.
    • Block spreadsheet formulas adds an apostrophe before cells that start with =, +, - or @, so a spreadsheet won't run them. Use it for data from untrusted sources.
  4. Press Copy or Download .csv.

Also accepted: a single object, a list of lists, and NDJSON (one object per line). If your list sits inside an object, like {"users": [...]}, the tool finds it.

CSV to JSON

Paste CSV and get a list of objects, using the first row as names. The separator is detected for you. Numbers, true and false become real JSON values, and empty cells become null; turn this off to keep everything as text. Values like 007 stay text so the zeros aren't lost.

Numbers are copied exactly in both directions, so long IDs are never rounded. Switching tabs moves your result across, ready to convert back.

Frequently asked questions

How do I open the CSV in Excel without broken accents?

Turn on Excel-friendly (BOM) before downloading. If Excel puts everything in one column, choose Semicolon as the separator, which is what Excel expects in many European countries.

What happens to nested objects and lists?

Nested objects become extra columns with dotted names, like address.city. Lists are written as JSON text in one cell, or joined with semicolons if you choose that.

Why are my long ID numbers changed in Excel?

This tool keeps numbers exact in the CSV, but Excel shows only 15 significant digits. Import the column as text in Excel to keep long IDs intact.

Related tools