How to Convert JSON to CSV or Excel — Free, No Signup

You have a JSON file. You need a spreadsheet. Here are the three ways to get there, fastest first — including one that never sends your data anywhere, which matters more than most people realise.

(If you're not sure what JSON actually is, two minutes with our plain-English explainer will make everything below obvious.)

Method 1: A Browser-Based Converter (Fastest)

Cocoon's free JSON Converter does the whole job in one screen:

1. Open mycocoon.life/json-converter
2. Paste your JSON, or drop the .json file onto the page
3. Preview the table it builds — each item becomes a row, each field a column
4. Download as CSV and open it in Excel, Google Sheets or Numbers

Two things make this the method we recommend:

• Everything runs in your browser. The file is never uploaded to a server. If your JSON contains customer records, employee data or anything under confidentiality rules, "no upload" isn't a nicety — it's the difference between converting a file and leaking one. Many popular converter sites process your file server-side; check before you paste.
• It validates as it converts. JSON breaks loudly — one stray comma and the file is invalid. The converter points at the problem instead of silently failing.

No signup, no file-size nagging, no watermark. It's part of Cocoon's set of free tools.

Method 2: Excel or Google Sheets Directly

Excel (Windows, Microsoft 365): Data → Get Data → From File → From JSON, then use Power Query's "To Table" and expand the columns. It works well, but Power Query's interface assumes you know what records and lists are — budget a few minutes of clicking the first time. Mac Excel's JSON support is patchier.

Google Sheets has no native JSON import. You'll need an Apps Script or a third-party add-on — at which point you're back to Method 1 with extra steps.

Use this method when the JSON import is something you'll repeat weekly on the same shaped file: Power Query remembers the transformation and re-applies it on refresh.

Method 3: Ask an AI (With One Caveat)

Pasting JSON into ChatGPT or Claude with "convert this to CSV" works for small files. Two caveats:

• Size: long files get truncated silently — you may receive 80 rows of your 300 and no warning.
• Privacy: you've just pasted your data into a third-party service. Same rule as Method 1: fine for harmless data, wrong for customer records.

Where AI genuinely shines is the weird cases — "flatten this so each order line is its own row, repeat the customer columns" — where you need judgement, not just conversion.

What About Nested JSON?

The one honest complication. If each item contains its own list (a customer containing orders), a flat table has to choose: one row per customer, or one row per order? No converter can read your mind — decide which level of the data is your row, and convert that. When in doubt, pick the most detailed level; you can always aggregate upward in a pivot table, but you can't disaggregate downward.

The 30-Second Summary

• One-off conversion: browser converter — 30 seconds, private, free
• Repeating weekly import: Excel Power Query
• Weird restructuring: AI, if the data is safe to share

And once the data is in a clean table, it becomes dramatically more useful as AI input too — that's the subject of Clean Data In, Better AI Out: Why File Formats Matter.