How do I convert a Parquet file to JSON without writing code?
Open the .parquet file in viewparquet and click Export → JSON. The conversion runs locally in your browser with DuckDB-WASM — no Python or install, and the data is never uploaded.
Converter
Convert Parquet to JSON
JSON is the format of APIs, fixtures, and debugging sessions — and Parquet’s nested structs, lists, and maps translate to it naturally, far better than they flatten into CSV.
viewparquet converts Parquet to JSON locally in your browser with DuckDB-WASM. Nothing uploads to any server. Open the file, optionally shape the output with SQL, and export newline-delimited JSON (one object per row) that streams into jq, log tools, and data loaders without further processing.
How to convert
Open the Parquet file
Drag your .parquet file into viewparquet, or open it from S3 or a URL.
Optionally query the slice you need
Nested columns can be exported as-is, or projected with dot notation (col.field) and UNNEST to reshape lists before export.
Export to JSON
Click Export and choose JSON. viewparquet writes JSON Lines — one JSON object per row — generated locally and downloaded straight from your browser.
Common questions
What happens to nested columns when converting Parquet to JSON?
They convert cleanly. Parquet structs become JSON objects, lists become arrays, and maps become objects — the nesting is preserved as-is. This is the main reason to prefer JSON over CSV for files with nested schemas.
Does the export produce a JSON array or JSON Lines?
viewparquet exports JSON Lines (NDJSON): one JSON object per line, one line per row. JSON Lines streams well and is what most data tools, log pipelines, and jq workflows expect. Wrapping into a single array is a one-liner afterwards if a tool requires it.
Is my data uploaded anywhere during the conversion?
No. Reading the Parquet file and writing the JSON both happen inside your browser tab via DuckDB-WASM. You can watch the DevTools Network panel while converting — nothing leaves your machine.
How do I do the same conversion from the command line?
With the DuckDB CLI: COPY (SELECT * FROM read_parquet('data.parquet')) TO 'data.json' (FORMAT JSON). Use the browser for quick one-offs and the CLI for repeatable scripts.
Related
Try it on your own file
Drop a Parquet, GeoParquet, CSV, or JSON file into viewparquet — browse rows, run DuckDB SQL, and export results, all locally in your browser. Nothing is uploaded.