LBS to KG Converter
Convert pounds to kilograms in one step. Enter a weight in lbs and get the exact value in kg, with the formula, examples and a quick-reference table below.
Kilograms = Pounds × 0.45359237
LBS to KG Formula
To convert pounds to kilograms, multiply the number of pounds by 0.45359237. Because the pound is defined in terms of the kilogram, this factor is exact. To convert kilograms to pounds, divide by 0.45359237, which is the same as multiplying by about 2.2046226218.
Pounds and Kilograms Explained
The pound (lb or lbs) is the main everyday unit of weight in the United States, and it is still heard in the UK for body weight and birth weights. The modern international avoirdupois pound is defined as exactly 0.45359237 kilograms, a value agreed by the English-speaking countries in 1959. One pound is divided into 16 ounces.
The kilogram (kg) is the base unit of mass in the metric (SI) system and is used for body weight, food and freight in most of the world. Since 2019 it has been defined through a fixed value of the Planck constant, and one kilogram contains 1,000 grams.
How to Convert Pounds to Kilograms
- Enter the weight in pounds. Decimals such as 154.3 are fine.
- The answer in kilograms appears instantly, or press Convert Now.
- Use Swap Units to convert kilograms to pounds, Copy Result to copy the answer, or Clear to start again.
Step-by-step by hand
- Write down the weight in pounds, for example 180 lbs.
- Multiply by 0.45359237: 180 × 0.45359237 = 81.6466266.
- Round to suit your purpose: 180 lbs ≈ 81.646627 kg (about 81.65 kg).
For a mental estimate, halve the pounds and then subtract about 10% of that half. For 180 lbs that is 90 − 9 = 81 kg, close to the exact answer. Ounces can be included by converting them to a fraction of a pound first (8 oz = 0.5 lb).
Mass cannot be negative, so this converter accepts zero and positive values only.
Practical Examples
- Body weight: 150 lbs × 0.45359237 = 68.038856 kg, and 200 lbs = 90.718474 kg.
- Airline baggage: a 50 lb checked-bag limit equals 22.679619 kg, and a 40 lb cabin limit is 18.143695 kg.
- Gym plates: a 45 lb plate weighs 20.411657 kg, and a 135 lb loaded bar is 61.23497 kg.
- Newborn: a baby of 7 lbs 8 oz (7.5 lbs) weighs 3.401943 kg.
- Groceries: a 5 lb bag of sugar is 2.267962 kg.
LBS to KG – Common Values
Quick reference for frequently used conversions
| Pounds (lbs) | Kilograms (kg) | Stone (st) |
|---|---|---|
| 1 lbs | 0.453592 kg | 0.0714 st |
| 2 lbs | 0.907185 kg | 0.1429 st |
| 5 lbs | 2.267962 kg | 0.3571 st |
| 10 lbs | 4.535924 kg | 0.7143 st |
| 15 lbs | 6.803886 kg | 1.0714 st |
| 20 lbs | 9.071847 kg | 1.4286 st |
| 25 lbs | 11.339809 kg | 1.7857 st |
| 35 lbs | 15.875733 kg | 2.5 st |
| 45 lbs | 20.411657 kg | 3.2143 st |
| 50 lbs | 22.679619 kg | 3.5714 st |
| 75 lbs | 34.019428 kg | 5.3571 st |
| 100 lbs | 45.359237 kg | 7.1429 st |
| 120 lbs | 54.431084 kg | 8.5714 st |
| 140 lbs | 63.502932 kg | 10 st |
| 150 lbs | 68.038856 kg | 10.7143 st |
| 160 lbs | 72.574779 kg | 11.4286 st |
| 180 lbs | 81.646627 kg | 12.8571 st |
| 200 lbs | 90.718474 kg | 14.2857 st |
| 250 lbs | 113.398093 kg | 17.8571 st |
Where and Why This Conversion Is Used
Pounds dominate daily life in the United States, while nearly every other country weighs people and goods in kilograms. The conversion comes up constantly.
- Health and fitness: weight-loss targets, BMI calculations and lifting records are often shared in pounds but calculated in kilograms.
- Travel: airlines may state baggage limits in pounds on US routes and kilograms elsewhere, and scales differ too.
- Shipping and e-commerce: US carriers and marketplaces list parcel weights in pounds, while international rates use kilograms.
- Medicine and childcare: birth weights, growth charts and weight-based dosing references may use either unit.
- Cooking and shopping: American recipes and packaging use pounds and ounces, while metric kitchens use grams and kilograms.
To go the other way see the KG to LBS Converter, or for small amounts try Pounds to Ounces.