1. SI vs Imperial Systems
The metric (SI) system is base-10 and globally dominant in science and engineering. Imperial units are still common in specific regions and industries, especially for feet/inches, pounds, and gallons.
2. Core Conversion Logic
Most conversions are linear ratios: multiply by source factor and divide by target factor. Temperature is different because it includes offset and scale changes (C/F/K).
3. Precision and Rounding
Use enough decimal places for technical contexts. For daily use, 2-3 decimals is usually enough. Avoid cascading conversions where repeated rounding can accumulate error.
4. High-Value Use Cases
- Construction: inch, ft, m transitions
- Fitness: lb/kg and fluid units
- Cooking: tsp, tbsp, cup, ml, liter
- Travel: mile/km and fuel volume
5. Common Mistakes
- Confusing US and UK gallon values
- Rounding too early in calculations
- Using integer-only conversion for temperature
- Ignoring unit symbols in datasets