Query CSV with SQL Online
Run SQL SELECT queries against a CSV in your browser: it loads into a table you can filter, group and join. Nothing is uploaded.
How to use the Query CSV (SQL)
- 01
Paste your CSV into the input; it loads into a table named data.
- 02
Write a SELECT query and press Run (or Ctrl/Cmd + Enter).
- 03
Copy or download the result as CSV.
What it does
This tool loads your CSV into a real SQLite table and lets you query it with SQL. Filter with WHERE, summarise with GROUP BY, sort, and shape the output exactly as you need.
It is the quickest way to answer a question about a spreadsheet without importing it into a database, and the result can be copied or downloaded as CSV.
How the CSV becomes a table
The header row becomes the column names and each row becomes a record in a table (named data by default, which you can change). Values that look numeric are stored as numbers so comparisons and sums work.
SQLite runs the query in your browser through WebAssembly, so joins, aggregates and subqueries all work and nothing is uploaded.
Private and unlimited
Every conversion happens locally in your browser, so your data is never uploaded, logged or stored on a server. You can use it on confidential exports without a second thought, and it keeps working offline once the page has loaded.
There is no sign-up, no watermark and no row limit: the only ceiling is your device's memory.
Frequently asked questions
What is the table called?
By default your CSV is loaded into a table named data, so a query like SELECT * FROM data works right away. You can rename it in the table field.
Which SQL is supported?
The full SQLite dialect, since it is the real engine compiled to WebAssembly: WHERE, GROUP BY, HAVING, ORDER BY, joins, subqueries and aggregate functions.
Is my CSV uploaded to run the query?
No. The CSV is parsed and queried entirely in your browser, so the data never leaves your device.
Is there a row or file-size limit?
There is no fixed row cap or daily quota. Because everything runs locally the practical limit is your device's memory, which comfortably handles the tens of thousands of rows most exports contain.
Is my data uploaded anywhere?
No. The conversion runs entirely in your browser with client-side JavaScript, so nothing you paste or drop ever leaves your device. That makes it safe for spreadsheets that contain customer emails, financial figures or other sensitive data.
Sources
Learn more
Query a CSV with SQL, No Database Setup Required
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