metric-trainer

A terminal drill program for getting a feel for the metric system if you grew up with imperial (or the reverse, I suppose). It asks you to convert a value, you type an answer, and it tells you whether you were close enough - within 1% by default, or 5% in easy mode, which also sticks to rounder numbers. There’s a --whole flag for whole numbers only.

Questions come from four categories - distance, weight, temperature, volume - in both directions, and you can practice any combination of them by typing the category letters together. Stats persist between sessions so you can see which category you’re worst at. It’s a small C program with no dependencies.

The code is here on GitHub.