How to Convert JSON to CSV

JSON is the lingua franca of APIs, but tools like Excel, Google Sheets, and most databases work best with CSV. Converting between the two is routine for analysts, developers, and anyone moving data out of an API response into a spreadsheet.

ThothBox's JSON to CSV converter turns your JSON into a clean, delimited table in the browser. Your data never gets uploaded, so even sensitive payloads are safe to convert locally.

Flat JSON converts cleanly

The simplest case is an array of flat objects, where every item has the same set of keys. Each object becomes a row and each key a column header, giving you a tidy CSV you can drop straight into a spreadsheet. This is the shape most API imports produce, and it converts without surprises.

Small mismatches between objects — some missing a field, others adding one — are handled by leaving the blank cells empty or adding the missing columns, so rows line up cleanly.

Nested JSON needs flattening

When values are themselves objects or arrays, they do not fit a flat table directly. The converter flattens them, joining nested keys into descriptive column names such as user.name or address.city. This keeps the data intact while still fitting the row-and-column shape of CSV.

Arrays inside an object are the trickiest case. An object with a list of children cannot be one clean row without collapsing, so the tool needs a rule for how to store that value — typically as a single cell or by widening the columns. Understanding this tradeoff helps you predict what the output looks like before you run it.

Mind the delimiter

CSV stands for comma-separated values, and commas are the default separator. But your data may itself contain commas, which means those values must be quoted so a spreadsheet does not split them into extra columns. The tool handles quoting for you, but it is worth checking that the delimiter matches what your target program expects.

If you plan to open your result in a spreadsheet, confirm it shows the expected columns. Occasionally a spreadsheet assumes a semicolon delimiter depending on region — knowing your destination prevents a confusing misread.

Step-by-step

  1. Open the JSON to CSV tool Go to the JSON to CSV page on ThothBox in any browser.
  2. Paste or load your JSON Add your JSON data. It is processed locally on your device.
  3. Choose conversion options Set the delimiter and how nested values should be handled.
  4. Run the conversion Start the process and let the tool build the rows and columns.
  5. Download the CSV Save your CSV file and open it in your spreadsheet to confirm the layout.

FAQ

Can I convert nested JSON to CSV?

Yes — nested keys are flattened into descriptive column names so the data still fits a table.

Is it free to convert JSON to CSV?

Yes, the converter is free and needs no account.

Is my data uploaded?

No. Conversion runs in your browser and your JSON never leaves your device.

What if my JSON objects have different keys?

Missing fields become empty cells and new keys become their own columns, so everything still lines up.

How do I set the CSV delimiter?

The tool lets you choose the separator to match what your spreadsheet or program expects.

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