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Flatten nested JSON objects, preview the columns, and download CSV without uploading the data.
Your checked result will appear here.
An object such as result.score becomes a dot-path header. The path preserves where the value came from while producing a flat table.
The same deterministic rules are applied in this browser. No model infers a schema or renames a field.
The root must be a non-empty array, and every row must be a JSON object.
Parent and child keys are joined with a dot, so result and score become result.score.
Keys first encountered anywhere in the array are added to one shared header row.
Quotes are doubled, complex cells are quoted, and formula-leading values receive an apostrophe.
This fixture is covered by the product test. The apostrophe before =2+2 is deliberate output, not source data.
[{"name":"Asha","result":{"score":92},"tags":["reviewed","local"],"unsafe":"=2+2"}]name,result.score,tags,unsafe Asha,92,"[""reviewed"",""local""]",'=2+2
{"name":"Asha"}A single object has no row boundary. Wrap records in an array before converting.
CSV has no native nested-object, array, null or type system. Review these conversions before importing the file.
result.score → result.scoreThe dot path becomes the column name; the leaf value becomes the cell.
["a","b"] → "[""a"",""b""]"The full array is encoded as a JSON string inside one CSV cell.
missing | null → empty cellThese states are indistinguishable after export, so preserve them another way if the distinction matters.
= + - @ → apostrophe prefixThe extra character reduces formula-execution risk when a spreadsheet opens the file.
Inspect the preview in the destination spreadsheet, especially when columns contain identifiers, dates, long numbers or multilingual text.