WhatTheDuck – open-source, in-browser SQL on CSV files

In plain words

WhatTheDuck is an open-source, in-browser tool that lets users run SQL queries directly on CSV files using DuckDB-Wasm. It's designed for developers and data analysts who need to quickly analyze CSV data without installing additional software. The tool runs entirely in the browser, making it accessible and lightweight for exploratory data analysis tasks.

written from the facts on this page · September 2026

From the sources

WhatTheDuck is an open-source web application built on DuckDB. It allows users to upload CSV and Parquet files, store them in tables, and perform SQL queries on the data. - GitHub - incentius-foss/WhatTheDuck: WhatTheDuck is an open-source web application built on DuckDB. It allows users to upload CSV and Parquet files, store them in tables, and perform SQL queries on the data.

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  WhatTheDuck – Browser-Based SQL Engine Powered by DuckDb on WASM2023 · whattheduck.incentius.com · ▲11

  WhatTheDuck is a free-to-use tool that allows you to run SQL queries on your CSV files right in your browser. No data is sent anywhere. We've leveraged the power of DuckDB over WASM to make this possible. Do try it out and hit us with any feedback.

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  SQL workbench in the browser2024 · sql-workbench.com · ▲117

  Free browser-based SQL editor powered by DuckDB. Query and visualize CSV, JSON, Parquet and Arrow files locally or from remote URLs. No installation required.

• CQ
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• DU
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