Weight

How many kg is 1 pound?

The pound has an exact metric definition, so this conversion has no rounding in it until you choose to round.

1 pound is exactly 0.45359237 kg, which rounds to 0.4536 kg. Going the other way, 1 kg is 2.20462 pounds. For everyday use, halve the pounds and subtract 10 per cent: 150 lb → 75 − 7.5 = 67.5 kg, against a true value of 68.04 kg.

Worked out 2026-09-10 (IST) · International avoirdupois pound, defined 1959

Pounds to kilograms

Common body weights, pounds to kg
Pounds	Kilograms	Stone and pounds
100	45.36	7 st 2 lb
110	49.90	7 st 12 lb
120	54.43	8 st 8 lb
130	58.97	9 st 4 lb
140	63.50	10 st 0 lb
150	68.04	10 st 10 lb
160	72.57	11 st 6 lb
170	77.11	12 st 2 lb
180	81.65	12 st 12 lb
200	90.72	14 st 4 lb
220	99.79	15 st 10 lb
250	113.40	17 st 12 lb

Kilograms to pounds

Common body weights, kg to pounds
Kilograms	Pounds	Stone and pounds
45	99.21	7 st 1.2 lb
50	110.23	7 st 12.2 lb
55	121.25	8 st 9.3 lb
60	132.28	9 st 6.3 lb
65	143.30	10 st 3.3 lb
70	154.32	11 st 0.3 lb
75	165.35	11 st 11.3 lb
80	176.37	12 st 8.4 lb
85	187.39	13 st 5.4 lb
90	198.42	14 st 2.4 lb
100	220.46	15 st 10.5 lb
110	242.51	17 st 4.5 lb

The mental shortcut. Pounds to kg: halve it, then take off ten per cent. Kg to pounds: double it, then add ten per cent. Both land within one per cent of the true value across the whole range of human body weight.

The formula

pounds → kg = pounds × 0.45359237

kg → pounds = kg ÷ 0.45359237 = kg × 2.2046226

stone → kg = stone × 6.35029318

Check your own numbers

Convert kilograms, pounds, stone, grams, ounces and tonnes in either direction.

Weight Converterkg, pounds, stone, grams, ounces and tonnes, converted both ways.

Frequently asked

How many pounds is 70 kg?

154.32 pounds, which is 11 stone 0.3 pounds in British usage. The conversion is 70 x 2.20462. If you only need a figure to talk about, 70 kg is "about 154 pounds" or "about 11 stone".

What is a stone in kg?

A stone is 14 pounds, so 6.35029 kg. British and Irish body weights are still quoted in stone and pounds: 11 stone 4 pounds is 158 pounds, which is 71.67 kg. The unit is not used in the United States, where body weight is given in pounds alone.

Is a pound the same everywhere?

The avoirdupois pound used for body weight and groceries is the same worldwide since the 1959 agreement: exactly 0.45359237 kg. Two older pounds still appear in specialist trades - the troy pound (373.24 g) for precious metals, and the apothecaries pound - but neither is used for anything you would weigh yourself on.

Why is 0.45359237 such an odd number?

Because the pound was defined first and the kilogram second, from unrelated starting points. When the two systems were reconciled in 1959, the choice was to fix the pound as an exact decimal fraction of the kilogram rather than the other way round, and 0.45359237 was the value that best matched the existing national standards. It has not changed since.

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