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📊 CSV Analytics Lab

Upload CSV files and query them with SQL. Run aggregations, JOINs, window functions — all in your browser.

DuckDB-WASM runs a full SQL engine in your browser. Paste CSV above, write a query, and click Run.

About this tool

CSV Analytics Lab lets you upload CSV data and query it with full SQL — aggregations, JOINs, WHERE filters, window functions, and group-by operations — all running inside your browser using DuckDB-WASM. No server, no upload, your data never leaves your machine.

Example: Given CSV data with columns name,age,city,score, you can run SELECT city, AVG(score) AS avg_score, COUNT(*) AS cnt FROM "data.csv" GROUP BY city ORDER BY avg_score DESC to see which city has the highest average score and how many people are in each group.

This is ideal for quick data exploration: filter rows with WHERE, join multiple CSV files, run statistical aggregations, and export results. DuckDB-WASM provides a full SQL engine that handles large datasets efficiently in the browser.

FAQ

What SQL features are supported?

DuckDB-WASM supports standard SQL including SELECT, WHERE, GROUP BY, HAVING, ORDER BY, LIMIT, JOINs (INNER, LEFT, RIGHT), subqueries, window functions (ROW_NUMBER, RANK, LAG/LEAD), aggregate functions (SUM, AVG, COUNT, MIN, MAX, STDDEV), string functions, date functions, and more.

How large a CSV can I analyze?

DuckDB-WASM is efficient but browser memory limits apply. Most datasets up to 50-100 MB work fine. The tool loads the CSV into an in-memory database, so available RAM is the main constraint.

Can I join multiple CSV files?

Yes. Upload or paste additional CSV data — each file referenced in your query becomes a table. Use standard SQL JOIN syntax like SELECT * FROM 'sales.csv' JOIN 'customers.csv' ON sales.customer_id = customers.id.

How is this different from the Data Table Viewer?

Data Table Viewer gives you sortable, filterable, paginated table browsing. CSV Analytics Lab gives you full SQL querying — aggregations, joins, window functions, and arbitrary SELECT expressions — for when you need to analyze data, not just view it.

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