What it does
Spreadsheets struggle once data has more than a few thousand rows, or when you need to combine two files. SQL handles both easily, but setting up a database just to ask a few questions takes time. This tool gives you a full SQLite database inside the browser tab. Open your files and each one becomes a table. You see a profile of every column straight away, and you can then ask questions in SQL. Your files are read on your device and never uploaded. The database disappears when you close the tab.
How to use it
- Open one or more CSV, TSV or Excel (.xlsx) files, or drop them on the box. Each sheet of an Excel file becomes its own table. The table name comes from the file name, for example
sales_2025. - Read the profile. For each column you see the type (whole number, number or text), how many cells are filled or missing, the number of distinct values, the minimum and maximum, the mean, and the three most common values. It is a quick way to spot typos, missing data and outliers before analysis.
- Write a query. A first query is suggested from your data. Press Run or Ctrl+Enter.
- Download the result as CSV, or copy it to paste into Excel. The page shows the first 1000 rows of a result, and the download has every row.
- A query that takes too long can be stopped. Your tables are then loaded again.
Good to know
- Empty cells and NA, N/A, null and #N/A count as missing (SQL NULL).
- Numbers with leading zeros, such as postcodes or IDs like 007, stay as text, so nothing is changed.
- Column names are kept as they are. Put names with spaces in double quotes:
"Unit price". - Files up to 150 MB each. Larger files work on a computer with plenty of memory, but phones may run out.
Worked example
Press Try it with sample data to load the Palmer penguins dataset (Horst, Hill and Gorman, CC0): 344 penguins from three islands in Antarctica. The profile shows 11 missing sex values. The suggested query SELECT species, COUNT(*) AS n, ROUND(AVG(bill_length_mm), 2) … GROUP BY species gives 152 Adelie, 124 Gentoo and 68 Chinstrap. Try SELECT island, sex, COUNT(*) FROM penguins WHERE sex IS NOT NULL GROUP BY island, sex next.
Frequently asked questions
Which SQL is this? SQLite 3, the most widely used database engine, compiled to WebAssembly. Window functions, CTEs (WITH), joins, and date and text functions all work.
Is my data safe? It stays in this browser tab. Nothing is sent anywhere, and the page works offline.
Turn a result into a figure with the publication plot maker, or tidy messy files first with the data cleaner.
Where the numbers come from
- Example table: Palmer Penguins data by Allison Horst, Alison Hill and Kristen Gorman (CC0).
Standard scientific values, such as constants, atomic weights and melting points, are facts found in every textbook; we name where ours were checked. If you are an author or publisher and want a value, a credit or a table changed or removed, tell us and we will act quickly.
Last updated 2026-11-08.