Tad

// WHAT IT'S FOR

Tad is a free, open-source desktop app for viewing and analyzing tabular data. It opens CSV and Parquet files and SQLite or DuckDB databases, even large ones, and lets you group them like a pivot table. Use it to go through a big sales or customer file without loading it into a spreadsheet. There are installers for Mac, Windows and Linux, and its author says it's a hobby project, so expect some bugs.