Once a CSV grows past a few thousand rows, filtering it in a spreadsheet gets painful — and the questions you want to ask ("top ten customers by total order value") are one line of SQL. The missing step is turning the CSV into a database.
The One-Step Version
Drop your file into the CSV to SQLite converter. It runs real SQLite — compiled to WebAssembly, inside your browser tab — and builds a proper .sqlite file:
- Your header row becomes column names ("Order Date" →
Order_Date) - Column types are inferred: all-integer columns become INTEGER, numeric ones REAL, everything else TEXT — so numeric sorting and aggregation work correctly
- Empty cells become NULL, and quoted values with commas are handled properly
The download opens in any SQLite client (DB Browser for SQLite, DBeaver, the sqlite3 command line), any ORM, or anything else that reads SQLite — which is nearly everything.
Coming From JSON Instead?
The JSON to SQLite converter does the same for JSON: an array of objects becomes a table, and an object of named arrays becomes a multi-table database. It accepts the exact shape produced by the SQLite to JSON export, so round trips work.
Why In-Browser Matters Here
Data files are exactly what you shouldn't paste into an unknown website: customer lists, order histories, logs. These tools never upload anything — SQLite itself runs on your device, and you can verify with the network tab that the file goes nowhere.
The Full SQLite Toolkit
Konverter also goes the other way: view a database's schema, or export to CSV or JSON. All the tools live on the database tools page.