Convert Nested JSON Objects to CSV Free
Overview
REST APIs commonly return nested objects like {user: {name: 'Alice', address: {city: 'Mumbai'}}}. Standard CSV converters truncate nested fields. This converter flattens one level of nesting using dot notation, turning user.name and user.address.city into separate columns.
How to Use This Tool
Paste your JSON with nested objects. Click Convert. The converter flattens up to two levels of nesting using dot notation. Review the column preview and download the CSV.
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PDF Tool →Frequently Asked Questions
How deep can the nesting be for the converter to handle it?
The converter reliably flattens up to two levels of nesting. Deeper nesting (three or more levels) converts the sub-object to a JSON string in the CSV cell rather than expanding it further.
What happens to arrays inside nested objects?
Arrays inside nested objects are serialized as JSON strings in the CSV cell. For example, tags: ['a','b'] becomes the string '["a","b"]' in the cell. Flatten arrays before converting if you need them as separate columns.
My JSON has both flat and nested objects in the same array. Will this work?
Yes. The converter unions all keys from all objects. Objects missing a key get an empty cell for that column. Nested keys appear as dot-notation columns for all rows, even those that did not have that field.