An imperial long hundredweight is 112 pounds.
Imperial hundredweights to Kilograms Converter — long cwt to kg
Convert Imperial hundredweight (long cwt) to Kilogram (kg) using the exact conversion factor (1 imperial hundredweight = 50.80234544 kilogram). See the formula, worked examples, conversion table, history, and common uses.
Imperial hundredweights to Kilograms converter
Converter
Mass/Weight Converter
Convert SI mass, imperial weight, jewelry, atomic, and astronomy mass units.
Context values
Some unit families need one extra value for a physically accurate result.
Kilogram is 1000 gram units.
Result = input x 50.80234544 / 1.
Mass uses the kilogram as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Imperial hundredweights to Kilograms
Weight conversions between Imperial hundredweight and Kilogram come up constantly in everyday commerce, shipping, and cooking, since US packaging is usually labeled in pounds while most of the rest of the world uses kilograms. Specifically: An imperial long hundredweight is 112 pounds, and kilogram is 1000 gram units.
Formula
kilograms = imperial hundredweights × 50.80234544
This factor comes from each unit's defined relationship to the category's base unit: 1 imperial hundredweight equals 50.80234544 base units, and 1 kilogram equals 1 base unit, so dividing one by the other gives the direct imperial hundredweight-to-kilogram factor of 50.80234544.
Simple example
1 long cwt × 50.80234544 = 50.80234544 kg
1 imperial hundredweight = 50.80234544 kilograms.
Real-world example
50 long cwt × 50.80234544 = 2,540.117272 kg
50 imperial hundredweights = 2,540.117272 kilograms.
Conversion table
| Imperial hundredweight (long cwt) | Kilogram (kg) |
|---|---|
| 1 long cwt | 50.80234544 kg |
| 5 long cwt | 254.0117272 kg |
| 10 long cwt | 508.0234544 kg |
| 25 long cwt | 1,270.058636 kg |
| 50 long cwt | 2,540.117272 kg |
| 100 long cwt | 5,080.234544 kg |
Reverse conversion: Kilogram to Imperial hundredweight
50.80234544 kg × 0.01968413055 = 1 long cwt
50.80234544 kilograms = 1 imperial hundredweight.
imperial hundredweights = kilograms × 0.0196841305522
For a page dedicated to this direction, see Kilogram to Imperial hundredweight.
Understanding the Imperial hundredweight (long cwt)
An imperial long hundredweight is 112 pounds.
Understanding the Kilogram
Kilogram (kg) measures mass. The kilogram is the SI base unit of mass; every other SI mass unit is a decimal multiple or fraction of it. It is classified as a SI base unit.
Where it's used: Used as the standard mass unit in nearly every country except the United States and a few others that primarily use the pound.
Uses of the Kilogram today
- Pricing and labeling goods sold by weight in retail and commodity trade
- Dosing calculations in medicine, especially for pediatric and weight-based prescriptions
- Structural and material specification in metric-system engineering
- Scientific measurement of mass across chemistry, physics, and materials research
History of the Kilogram
The kilogram's direct predecessor was the 'grave,' defined by the French Academy of Sciences in 1793 as the mass of one cubic decimeter of water at its temperature of maximum density. Because 'grave' echoed the aristocratic title 'graf,' revolutionary France's decree of 18 Germinal, Year III (7 April 1795) renamed the system: the gram became the reference unit, defined as the mass of one cubic centimeter of water at the melting point of ice, and the kilogram — one thousand grams — took over the grave's practical role.
Turning that water-based definition into a physical object required real experimental work: chemist Louis Lefèvre-Gineau was tasked in 1795 with measuring precisely how much a cubic decimeter of water weighed, and former royal jeweller Marc-Étienne Janety then fabricated a platinum cylinder to embody that measured mass. Deposited in the French National Archives in 1799, it became known as the Kilogramme des Archives.
The metric system spread unevenly — Napoleon briefly restricted its use — but France made it compulsory in 1840, and the 1875 Metre Convention (signed by seventeen nations including the US) established the BIPM and a shared international prototype. The platinum-iridium International Prototype of the Kilogram, adopted in 1889 and nicknamed 'Le Grand K,' served as the world's mass reference for over a century.
On 20 May 2019, the kilogram was redefined by fixing the Planck constant at exactly 6.62607015 × 10⁻³⁴ joule-seconds, so it can now be realized in a laboratory (via a Kibble balance) without reference to any physical object.
Historical origin. Kilogram was not the invention of a single named person; it developed through the process described above.
Kilogram — sources
- BIPM — The kilogram (SI base unit) — Official definition and history since the 2019 redefinition.
- NIST — Kilogram: The Past — History of the kilogram standard from the grave to the International Prototype Kilogram.
- SI Brochure, 9th edition (2019), Appendix 2 — BIPM — Official text of the Planck-constant-based definition of the kilogram.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilograms are in 1 imperial hundredweight?
1 imperial hundredweight equals 50.80234544 kilograms, using the exact defined conversion factor rather than an estimate.
How do I convert imperial hundredweight to kilogram?
Multiply the imperial hundredweight value by 50.80234544. The converter above does this instantly to whatever precision you set.
How do I convert kilogram back to imperial hundredweight?
Use the reverse factor: 1 kilogram equals 0.0196841306 imperial hundredweights. You can also use the swap control in the converter above to flip the direction instantly.
What is a imperial hundredweight?
Imperial hundredweight (long cwt) is a unit of mass/weight.
What is a kilogram?
Kilogram (kg) measures mass. The kilogram is the SI base unit of mass; every other SI mass unit is a decimal multiple or fraction of it. It is classified as a SI base unit.
Is the imperial hundredweight to kilogram conversion exact?
Yes. Both imperial hundredweight and kilogram are defined by fixed standards rather than physical artifacts, so the factor of 50.80234544 used above is exact to as many digits as you choose to display.