Focused purpose
What this tool does
Convert JSON arrays or NDJSON to CSV locally. Flatten nested objects with path notation, review arrays and missing keys, then download without an account.
- ✓ Object arrays and NDJSON
- ✓ Nested object flattening
- ✓ Path-based headers
- ✓ Missing-key alignment
Workflow
How to use it
- 01
Open a JSON array or NDJSON stream.
- 02
Review flattened paths and array warnings.
- 03
Choose delimiter and export the table.
Available controls
Available options
- Choose dot or custom path notation.
- Serialize, join or reject nested arrays.
- Select comma, semicolon or tab output.
- Review the union of all keys.
Nested people objects
Example before and after
Nested properties and a missing city need a stable flat schema.
Before
[{"id":"0001","person":{"name":"Ada","city":"Paris"}},{"id":"0002","person":{"name":"Linus"}}]After
id,person.name,person.city 0001,Ada,Paris 0002,Linus,
Expected result: Dot paths become columns and the missing key becomes an empty field.
Practical scenarios
Common use cases
Open API data in a spreadsheet.
Flatten event logs.
Turn NDJSON exports into tabular files.
HONEST LIMITS
Important limitations
- iDeep or heterogeneous arrays do not have one universal tabular representation.
- iObject key order does not define the final schema; the preview does.
FAQ
Questions about this tool
Can nested JSON be converted?
Yes. Nested objects flatten to path-based columns shown before export.
What happens to nested arrays?
Choose to serialize them as JSON, join simple values or stop and review.
Can I paste NDJSON?
Yes. Each non-empty line is parsed as one object and aligned to the union schema.