100 lbs to kg

How to convert 100 lbs to kg

A pound is defined as exactly 0.45359237 kilogram, so multiply:

100 lb × 0.45359237 = 45.36 kg

Dividing by 2.20462 gives the same answer. The converter above starts at 100 lb and has a second field for ounces; type a different number and the kilograms follow, or use the full lbs to kg converter. To go the other way, see kg to lbs.

100 lbs in kilograms and grams, and in stone

The 0.36 after the whole kilograms is a fraction of a kilogram: 0.3592 × 1,000 = 359.2 grams. So 100 pounds is:

• 45 kg 359 g — the way a metric scale or a parcel form reads;
• 45,359 g — in grams;
• 7 st 2 lb — the British way of stating weight (100 ÷ 14).

The result block shows all of these for whatever you enter. 100 lb is the U.S. hundredweight (short hundredweight), used for grain, livestock and freight prices, and it equals 45.36 kg. The British hundredweight is 112 lb, or 50.80 kg.

Nearby values

From 10 to 200 lb:

Rounded for display, 100 lb is 45.4 kg on a scale with one decimal and 45 kg on one that shows whole kilograms. Going the other way, 45 kg is 99.2 lb, so a reading of 45 kg on a metric scale is 0.8 lb less than 100 lb.

100 pounds and some ounces

Scales in the U.S. often read pounds and ounces. Each ounce is 28.35 grams, so the ounces matter at this weight only in the first decimal:

100.25 lb is 100 lb 4 oz, 100.5 lb is 100 lb 8 oz and 100.75 lb is 100 lb 12 oz. Type the ounces into the second field to convert an exact reading.

A quick rule for your head

Halve the pounds, then take away 10% of that: 100 ÷ 2 = 50, and 50 − 5 = 45 kg. The rule is about 0.8% low — here 0.36 kg. Halving alone (50 kg) is 4.64 kg too high. Because 100 lb is a round number, 45.359237 kg is also the exact kilogram value of a pound times 100. For smaller weights, use ounces to grams.