Converters
Weight Converter
Last updated: June 19, 2026
A weight converter is a measurement utility that translates mass and weight values between different metric and imperial units. The calculator supports conversions between metric units (such as milligrams, grams, kilograms, and metric tonnes) and imperial units (such as ounces, pounds, stone, and US tons). It applies standard conversion factors, including one kilogram equals two point two hundred four pounds, to guarantee precision. Students, chefs, shippers, and travelers use this tool to standardize weights for shipping, cooking, and academic tasks.
Pick a 'from' unit, a 'to' unit, and enter a value. The calculator returns the converted result plus a table of equivalents in every supported mass unit.
Quick Answer
Convert weights and mass values between metric and imperial systems. Enter your value and select units for quick conversions across grams, kilograms, ounces, and pounds.
Weight cannot be negative. · e.g. 1
Internal base unit is the kilogram. US ton = 2,000 lb; imperial (long) ton = 2,240 lb.
Kilogram → Pound
2.204623 lb
1 kg = 2.204623 lb
Conversion factor (relative to kilogram): 1 kg = 1 kg · 1 lb = 0.45359237 kg.
Examples
1 kg to pounds
≈ 2.205 lb
180 lb to kilograms
≈ 81.647 kg
12 stone to kg
= 76.2035 kg
How it works
All units are stored as factors relative to the kilogram. Convert through the kilogram base: value times source factor gives kilograms, then divide by target factor.
Formula · output = value × factor(from) ÷ factor(to)
Common factors: 1 oz = 28.3495 g · 1 lb = 0.453592 kg · 1 stone = 6.35029 kg · 1 t = 1,000 kg · 1 US ton = 907.18 kg · 1 imperial ton = 1,016.05 kg.
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Frequently asked questions
In physics, mass and weight are distinct (mass is amount of matter; weight is force from gravity). In everyday use the terms are interchangeable for objects on Earth's surface. The calculator handles the everyday case: it converts between mass units that are used in the same way.
US ton (short ton) = 2,000 lb ≈ 907.18 kg. Imperial ton (long ton) = 2,240 lb ≈ 1,016.05 kg. Both are different from the metric tonne (t) = 1,000 kg ≈ 2,204.62 lb. Use the label that matches your context.
Yes, since 1959. The international pound is defined as exactly 0.45359237 kg. Before standardization there were slight regional differences, but for modern use treat the pound as exactly 0.453592 kg.
Stone (st) is a British unit equal to 14 pounds (about 6.35 kg). It's commonly used for body weight in the UK and Ireland. 'I weigh 12 stone 3' means 12×14 + 3 = 171 lb, or about 77.6 kg.
It does, but the pet weight converter is a more focused tool with helpful framing for pet owners (puppy/kitten ranges, common pet-weight scales). For general-purpose mass conversion this tool is the right pick.
Below about 0.0001 or above 1 billion, the calculator switches to scientific notation (e.g., 1.234e+10) so the meaningful digits stay visible. For everyday weights you'll see standard formatting.
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