Baggage, bodyweight and fitness apps
The baggage-limit conversion — 23 kg check-in ≈ 50.7 lb (why US airlines round to 50 lb), 7 kg cabin ≈ 15.4 lb. Fitness world: 1 kg = 2.20462 lb, so a 100 kg deadlift = 220.5 lb (or the more commonly-quoted 225 lb ≈ 102 kg — two 45 lb plates plus the bar). US medical charts still show weight in lbs even in metric countries; European gym plate stacks in kg confuse people trained on US machines.