Enter the value to convert into the box and modify the accuracy of the conversion by selecting number of significant figures or decimal places by clicking on the boxes provided.
The conversion formula for kilograms (kg) to pounds (lb) conversions is as follows:
The conversion formula for pounds (lb) to kilograms (kg) conversions is as follows:
The kilogram is the base unit of mass in the SI system of units. The kilogram is defined by the International Prototype Kilogram (IPK) and is the only metric base unit to be defined by an artifact and to have a prefix (kilo).
SI Metric
The kilogram is defined as the mass of the International Prototype Kilogram held in a vault by the International Bureau of Weights and Measures in Sèvres, France. The International Prototype Kilogram (IPK) is a block of platinum-iridium alloy held under controlled conditions and designed to reduce potential wear.
kilogram
The kilogram is the base unit of mass in the SI metric system, even though it would appear from its name to be a subsidiary unit of the gram.
Formal: kg
Alternates: kilo, kilos
The abbreviations kilo and kilos are often used on food displays where produce is bought loose in kilograms and grams.
Many european countries use the alternate spelling kilogramme, which came from the French. The kilogramme was originally defined in Law in France in 1795. The spelling kilogram was an americanisation of the original word that then became common in other English speaking countries such as the UK, Canada and Australia. The french word was derived from the greek words chilloi (thousand) and gramma (small weight).
The first definition of the kilogram came from the gram (even though the kilogram is now the base unit, this came about as most trade and commerce is carried out in weights larger than the gram), the gram being defined as the weight of a cubic centimetre of water at the temperature of melting ice.
The first prototype kilogram was made in 1799 of platinum, the current IPK was made in 1879 and was formally adopted as the kilogram by the General Conference on Weights & Measures at their first meeting in 1889.
Currently there are plans for a redefinition of the kilogram in terms of physical properties that can reproduced in many laboratories in order to replace the IPK.
The kilogram is recognised as the standard unit of weight around most of the world, exceptions being the United States and Liberia. In science the kilogram is used as the unit of mass across the globe.
The pound is the base unit of the avoirdupois weight system and since the International Pound and Yard agreement of 1959 has been defined in terms of the SI metric kilogram.
The pound has it roots in Roman weights and the avoirdupois pound (as opposed to the Troy and obsolete pounds) has been in use in Britain from about 1300 AD, at that time it was also called the wool pound.
Avoirdupois - British Imperial & US Customary
The pound is defined as 0.45359237 kilograms following the International Yard and Pound Agreement of 1959.
Kilogram - however the pound is the base unit of the avoirdupois weight system.
Formal: lb
Alternates: lbs, lbm
lbs is often seen for a number of pounds above one and lbm is used to indicate pound-mass in situations where mass does not necessarily equal weight.
The avoirdupois pound that is currently in use in the USA and is also used informally in Britain and various British Commonwealth countries has its roots in the Roman weight the libra. From about 1300 AD the avoirdupois pound (sometimes referred to as the wool pound in England) came into general use and before the reign of Elizabeth the first was equivalent to 6,992 troy grains.
An act of parliament in Elizabethan times redefined the pound as 7,000 troy grains and standards were produced to be held by the treasury.
The pound escaped any change under the Weights and Measures act of 1824 and has remained the same as in the times of Elizabeth the first. It is used as the basis for the British Imperial system of weights and the US Customary system of weights, that split off from the British system at the time of US Independence.
Following the Act of 1824 another standard pound was produced, after a fire at the Houses of Parliament, this was a platinum cylinder which remained the formal definition of the pound until the 1963 Weights and Measures Act that introduced the current definition of the pound in terms of the metric kilogram.
An 1878 Weights and Measures Act had defined the kilogram for use in British law as being 453.59265 grams. This was legally refined to 0.45359243 kilograms in 1898. The 1963 Weights and Measures act reversed the legal relationship between the pound and the kilogram in Britain defining the pound in terms of the kilogram.
The pound is in statutory use in the United States and is informally used in the United Kingdom and British Commonwealth countries, such as Australia, Cannada, Jamaica, New Zealand and South Africa.
| kg | lb |
| 1 | 2.20 |
| 2 | 4.41 |
| 3 | 6.61 |
| 4 | 8.82 |
| 5 | 11.02 |
| 6 | 13.23 |
| 7 | 15.43 |
| 8 | 17.64 |
| 9 | 19.84 |
| 10 | 22.05 |
| kg | lb |
| 10 | 22.05 |
| 20 | 44.09 |
| 30 | 66.14 |
| 40 | 88.18 |
| 50 | 110.23 |
| 60 | 132.28 |
| 70 | 154.32 |
| 80 | 176.37 |
| 90 | 198.42 |
| 100 | 220.46 |
| kg | lb |
| 100 | 220.46 |
| 200 | 440.92 |
| 300 | 661.39 |
| 400 | 881.85 |
| 500 | 1,102.31 |
| 600 | 1,322.77 |
| 700 | 1,543.24 |
| 800 | 1,763.70 |
| 900 | 1,984.16 |
| 1,000 | 2,204.62 |
| lb | kg |
| 1 | 0.45 |
| 2 | 0.91 |
| 3 | 1.36 |
| 4 | 1.81 |
| 5 | 2.27 |
| 6 | 2.72 |
| 7 | 3.18 |
| 8 | 3.63 |
| 9 | 4.08 |
| 10 | 4.54 |
| 11 | 4.99 |
| 12 | 5.44 |
| 13 | 5.90 |
| 14 | 6.35 |
| lb | kg |
| 14 | 6.35 |
| 28 | 12.70 |
| 42 | 19.05 |
| 56 | 25.40 |
| 70 | 31.75 |
| 84 | 38.10 |
| 98 | 44.45 |
| 112 | 50.80 |
| lb | kg |
| 25 | 11.34 |
| 50 | 22.68 |
| 75 | 34.02 |
| 100 | 45.36 |
| 125 | 56.70 |
| 150 | 68.04 |
| 175 | 79.38 |
| 200 | 90.72 |