Local DuckDB SQL Explorer

Load a local Parquet, CSV or JSON file and query it with DuckDB WebAssembly. No remote datasets or third-party CDN.

Local: yes. Your input stays on your device and is not sent to an external service for this tool.

Local dataset

Choose Parquet, CSV or JSON (max 100 MB)

Choose a file to start.

Query table: data

SQL query (read-only)

SELECT * FROM data LIMIT 10

Engine files are served by GratisTools. Uploaded files remain in browser memory. Only read-only local SELECT queries are accepted; results are capped at 500 rows.

Why DuckDB in the browser?

DuckDB queries columnar Parquet, CSV and JSON files locally, so you can filter, aggregate and explore tables with SQL without first uploading them. The WebAssembly engine and worker are hosted on GratisTools and loaded only when you open a file.

Limits and safety

One input dataset, up to 100 MB, local SQL only, no extensions or external URL reading, and a maximum of 500 returned rows. Very large Parquet files may exceed mobile device memory. This is not a remote SQL service; nothing is stored to your account.

Frequently asked questions

Is this tool free?

Yes. The core tool is free to use in your browser.