JSON to CSV Converter

A proper converter — not a quick-and-dirty one. Flattens nested objects to dot-paths, joins primitive arrays with a pipe, handles heterogeneous keys, and quotes fields automatically when needed.

Built for engineers prepping JSON dumps for analytics pipelines.

1. Load JSON into the converter

Accepts array-of-objects or object-of-arrays. Mongo Extended JSON ({"$date":...}, {"$oid":...}) flattens to two columns.

2. Configure separator + flattening

Pick your separator, toggle Quote-All when values contain commas, and the converter handles nested dot-paths automatically.

3. Download result as CSV

The output is an RFC 4180-compliant CSV ready for pandas, Excel, Postgres COPY, BigQuery ingest, or csvkit.

How are nested objects flattened in the converter?

Each nested key becomes a dot-path column: {"user": {"name": "Ada"}} yields a user.name column. Arbitrary depth supported.

Does the converter work on MongoDB Extended JSON?

Yes. {"$date": ...} and {"$oid": ...} wrappers flatten to two columns — strip them with jq before paste if you want the plain value.

What about Firestore "fields" exports?

Extract the `fields` array first, then paste. Native Firestore-shape handling is on the roadmap.

Does the converter preserve array values inside JSON?

Primitive arrays (strings, numbers) are joined with a pipe: ["red","green"] → red|green. Arrays of objects are skipped with a warning.