To convert kilograms to pounds, multiply by 2.20462. So 1 kg is 2.2 lb, 50 kg is 110.2 lb and 70 kg is 154.3 lb. To go from pounds to kilograms, multiply by 0.45359237, which is exact: that’s how the pound is defined.
Where does 2.20462 come from? #
Since 1959, the international avoirdupois pound has been defined as exactly 0.45359237 kg. The US and the Commonwealth countries agreed on it together with the international yard, and the same figure is written into UK law in the Weights and Measures Act 1985.
So pounds to kilograms is exact. Kilograms to pounds is the reciprocal, 1 ÷ 0.45359237 = 2.2046226218…, and the decimals never end. Every kg-to-lb figure you see is rounded somewhere. Five decimal places (2.20462) are more than any bathroom or luggage scale can use.
The mental shortcut #
Double it, then add 10%. For 70 kg: double to 140, add 14, and you get 154 lb. The exact answer is 154.32, so the shortcut is about 0.2% low, less than the error of most home scales.
Going back, divide by 2.2, or halve the pounds and subtract 10%. The second version is quicker but runs about 1% low: 154 lb halves to 77, minus 7.7 gives 69.3 kg against the exact 69.85.
kg to lbs chart #
| kg | lb (decimal) | lb and oz | stone |
|---|---|---|---|
| 1 | 2.20 | 2 lb 3.3 oz | 0.16 |
| 2 | 4.41 | 4 lb 6.5 oz | 0.31 |
| 3 | 6.61 | 6 lb 9.8 oz | 0.47 |
| 5 | 11.02 | 11 lb 0.4 oz | 0.79 |
| 10 | 22.05 | 22 lb 0.7 oz | 1.57 |
| 20 | 44.09 | 44 lb 1.5 oz | 3.15 |
| 23 | 50.71 | 50 lb 11.3 oz | 3.62 |
| 25 | 55.12 | 55 lb 1.8 oz | 3.94 |
| 30 | 66.14 | 66 lb 2.2 oz | 4.72 |
| 40 | 88.18 | 88 lb 3.0 oz | 6.30 |
| 50 | 110.23 | 110 lb 3.7 oz | 7.87 |
| 55 | 121.25 | 121 lb 4.1 oz | 8.66 |
| 60 | 132.28 | 132 lb 4.4 oz | 9.45 |
| 65 | 143.30 | 143 lb 4.8 oz | 10.24 |
| 70 | 154.32 | 154 lb 5.2 oz | 11.02 |
| 75 | 165.35 | 165 lb 5.5 oz | 11.81 |
| 80 | 176.37 | 176 lb 5.9 oz | 12.60 |
| 85 | 187.39 | 187 lb 6.3 oz | 13.39 |
| 90 | 198.42 | 198 lb 6.7 oz | 14.17 |
| 95 | 209.44 | 209 lb 7.0 oz | 14.96 |
| 100 | 220.46 | 220 lb 7.4 oz | 15.75 |
| 120 | 264.55 | 264 lb 8.9 oz | 18.90 |
| 150 | 330.69 | 330 lb 11.1 oz | 23.62 |
lbs to kg chart #
| lb | kg | lb | kg | |
|---|---|---|---|---|
| 1 | 0.45 | 120 | 54.43 | |
| 5 | 2.27 | 130 | 58.97 | |
| 10 | 4.54 | 140 | 63.50 | |
| 20 | 9.07 | 150 | 68.04 | |
| 25 | 11.34 | 160 | 72.57 | |
| 30 | 13.61 | 170 | 77.11 | |
| 40 | 18.14 | 180 | 81.65 | |
| 50 | 22.68 | 200 | 90.72 | |
| 100 | 45.36 | 250 | 113.40 |
Why is 6.61 lb not 6 lb 6 oz? #
Decimal pounds and pounds-and-ounces are different notations, and mixing them up is the most common kg-to-lb mistake. There are 16 ounces in a pound, not 10. So 6.61 lb is 6 pounds plus 0.61 of a pound, and 0.61 × 16 = 9.8 ounces. A 3 kg newborn weighs 6 lb 9.8 oz, not 6 lb 6 oz.
To split a decimal: keep the whole pounds, multiply the decimal part by 16 for ounces.
Converting kg to stone #
In the UK and Ireland, people often give body weight in stone and pounds. One stone is 14 lb, which is exactly 6.35029318 kg. To convert:
- Convert kg to pounds (× 2.20462).
- Divide by 14. The whole number is stone.
- Multiply the remainder by 14 for the leftover pounds.
For 70 kg: 154.32 lb ÷ 14 = 11.02, so 11 stone, and 0.02 × 14 ≈ 0.3 lb. Call it 11 st 0 lb.
Worked examples #
Your checked bag weighs 23 kg. That’s 50.7 lb, which is why luggage allowances quoted as 23 kg and 50 lb are treated as the same limit.
A gym has 20 kg plates and you think in pounds. Each is 44.1 lb. A standard 45 lb plate is 20.4 kg, so they’re near enough interchangeable for loading a bar.
A recipe from the UK calls for 1.5 kg of potatoes. 1.5 × 2.20462 = 3.3 lb, a bit over a 3-pound bag.
A US shipping label says 12 lb. 12 × 0.45359237 = 5.44 kg.
Is a kilogram a unit of mass or weight? #
Strictly, the kilogram is a unit of mass, and the everyday pound (the avoirdupois pound) is too. In daily life, “weight” means mass, and scales report it in kg or lb. Engineers use a separate unit, the pound-force, for force. If you’re converting body weight, food, luggage or freight, kg to lb is the right conversion.
Converting kg and lbs on your phone #
Convert Units Calculator has a Weight category with milligrams, grams, kilograms, metric tons, ounces, pounds and US short tons, using the exact 0.45359237 kg pound. Type a figure in kilograms and every other unit appears under the result as you type, so pounds, ounces and grams are all on screen together. Version 1.0.5 adds a keypad that does arithmetic in the value field, which helps at the gym: type 2*20+20 for two 20 kg plates on a 20 kg bar and read 132.3 lb.
Related conversions: grams to ounces for food and postage, ton vs tonne for heavy loads, and how to convert units if you want the method behind all of these.
Frequently asked questions #
How many pounds is 1 kg? #
1 kg is 2.20462 lb, usually rounded to 2.2 lb. In pounds and ounces it’s 2 lb 3.3 oz.
What is 70 kg in pounds? #
70 kg is 154.32 lb, or 154 lb 5 oz. In stone, it’s 11 stone and about a third of a pound.
Is it accurate to multiply by 2.2? #
It’s close enough for everyday use. Multiplying by 2.2 gives a result about 0.2% low, which is 0.3 lb on a 70 kg person. Use 2.20462 when accuracy matters, such as for shipping or medication weights.
How many kg is 100 lb? #
100 lb is 45.36 kg. Multiply by 0.45359237, the exact definition of the pound.
How many kg is a stone? #
One stone is 14 lb, which is 6.35 kg (exactly 6.35029318 kg).