Gym weights in lbs and kg
In many gyms, plates and dumbbells are marked in pounds. A standard 45 lb plate is 20.41 kg, a 25 lb plate 11.34 kg and a 2.5 lb plate 1.13 kg. A US barbell weighs 45 lb (20.41 kg), close to the 20 kg Olympic bar, which is 44.09 lb. The classic milestones of one, two and three plates per side, 135, 225 and 315 lb, are 61.23, 102.06 and 142.88 kg.
If you follow a training plan written in pounds but lift in kilograms, convert the total and round to the plates you have: steps of 2.5 kg are close to steps of 5 lb.
Body weight, luggage and babies
US body weights are given in pounds: 150 lb is 68.04 kg and 200 lb is 90.72 kg. An airline limit of 50 lb for checked bags equals 22.68 kg, a little under the 23 kg used by many other airlines. Birth weights are often given in pounds and ounces: 7 lb 8 oz is 7.5 lb, which is 3.40 kg. For British weights in stones, pick Stones in the From list (1 stone is 14 lb, or 6.35 kg).