What does flattening a JSON object mean, and why would I do it?

Flattening a JSON object converts a deeply nested structure into a single-level object where each key is a dot-notation path to the original value. For example, {"user":{"address":{"city":"Rome"}}} becomes {"user.address.city":"Rome"}. This is useful for loading JSON into a spreadsheet (CSV), indexing into a search engine, or processing in a flat relational database.

How are nested keys represented after flattening?

Keys are joined with dots: {"a":{"b":{"c":1}}} becomes {"a.b.c":1}. Array elements use their index: {"items":["x","y"]} becomes {"items.0":"x","items.1":"y"}. This matches the convention used by Lodash's _.get() path syntax.

Does JSON flatten handle arrays inside the JSON?

Yes. Array elements are flattened using their numeric index as the key component (items.0, items.1, etc.). Nested arrays are recursively flattened in the same way.

Is JSON flatten useful for converting to CSV?

Yes — it is actually one of the most common workflows. Use JSON Flatten first to make every value a top-level key, then use JSON to CSV to convert the flattened JSON into a spreadsheet with one column per key.

Is the JSON flatten tool free and private?

Yes — completely free, no account, and runs in your browser.

JSON flat

JSON Flatten

Flatten nested JSON objects into a single-level structure with dot-notation keys.

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