UK weight-loss calculator
100 kg in stone and pounds
100 kilograms is 15 st 10.5 lb. Below: how that is worked out, and what it means at your height.
Updated
kg = st lb
Displayed values are rounded for readability, but the arithmetic uses the full precision of the internationally defined factors, a pound is exactly 0.45359237 kg and a stone is exactly 14 pounds, so converting back and forth will not drift.
Kilograms to Stone and pounds
15 st 10.5 lb
100 kg converts to the figure on the left, exactly. Nothing in it is an approximation.
Converting 100 kg
100 kilograms is 15 st 10.5 lb. A stone is 14 pounds and a kilogram is about 2.2046 pounds, so 100 kg is 220.5 lb, which is 15 whole stone with 10.5 lb left over.
Most converters stop at a decimal stone, which is not a unit anybody says out loud. 15 st 10.5 lb is the form you would use. In pounds alone it is 220.5 lb.
Between which whole stone
100 kg is 10.5 lb past 15 stone and 3.5 lb short of 16. 15 st exactly is 95.3 kg; 16 st is 101.6 kg. If you weigh yourself in stone, those are the two numbers either side of you.
What 100 kg means at different heights
At none of the heights below does 100 kg fall inside the range the NHS calls a healthy weight. It reads as obese (class 3) at 5 ft 0 in and overweight at 6 ft 2 in, a BMI of 43.1 down to 28.3.
| Height | BMI | NHS category | From healthy range |
|---|---|---|---|
| 5 ft 0 in | 43.1 | Obese (class 3) | 42.1 kg over |
| 5 ft 2 in | 40.3 | Obese (class 3) | 38.2 kg over |
| 5 ft 4 in | 37.8 | Obese (class 2) | 34.1 kg over |
| 5 ft 6 in | 35.6 | Obese (class 2) | 30.0 kg over |
| 5 ft 8 in | 33.5 | Obese (class 1) | 25.6 kg over |
| 5 ft 10 in | 31.6 | Obese (class 1) | 21.2 kg over |
| 6 ft 0 in | 29.9 | Overweight | 16.6 kg over |
| 6 ft 2 in | 28.3 | Overweight | 11.9 kg over |
100 kg sits above the healthy range at every height here, by 11.9 kg at 6 ft 2 in rising to 42.1 kg at 5 ft 0 in. That last column is the gap to the top of the band, which is not the same as how much anyone should aim to lose.
Losing 5 to 20% of 100 kg
Weight-loss advice is usually quoted in percentages, which is hard to picture. From 100 kg, this is what each of those marks comes to.
| Reduction | Weight lost | New weight | In stone and pounds |
|---|---|---|---|
| 5% | 5 kg | 95 kg | 14 st 13.4 lb |
| 10% | 10 kg | 90 kg | 14 st 2.4 lb |
| 15% | 15 kg | 85 kg | 13 st 5.4 lb |
| 20% | 20 kg | 80 kg | 12 st 8.4 lb |
The weight loss calculator estimates how long reaching one of those could take at a safe pace, and the weight loss percentage calculator works the other way round, turning weight already lost into a percentage.
BMI is a screening measure, not a diagnosis, and it says nothing on its own about how healthy you are. It does not know how much of you is muscle, and the thresholds are lower for some family backgrounds. What your BMI does and does not say.
The values either side
Scales rarely land on a whole number, and the one you want is often a kilogram either way.
- 98 kg in stone15 st 6.1 lb
- 99 kg in stone15 st 8.3 lb
- 101 kg in stone15 st 12.7 lb
- 102 kg in stone16 st 0.9 lb
For the conversion in the other direction, or for the full chart, see stone to kg and the kg to stone converter. To put this weight to work, the BMI calculator takes your own height rather than the eight above.