SQL Playground
Drop CSV, TSV, JSON, Parquet or Excel files and query them with real SQL — joins across files, GROUP BY, window functions, CTEs, the whole language — powered by DuckDB compiled to WebAssembly. Browse the schema, page through results, chart them, and export the answer as CSV or JSON. A sample dataset is included, so you can start writing queries before uploading anything.
Runs 100% in your browser — your files never leave your device.
Read the full guide to this tool
Notes
- The query engine (DuckDB compiled to WebAssembly, about 35 MB) is downloaded from a CDN on first use, then cached by your browser.
- Each file becomes a table named after the file. DuckDB speaks standard SQL plus its analytics extensions: window functions, QUALIFY, PIVOT, list and struct types, and direct functions like read_csv_auto().
- Memory is the only real limit: files are loaded into RAM, so multi-gigabyte inputs may fail where a desktop database would page to disk.
- Runs 100% in your browser — your files and data never leave your device.
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