About the Mass Converter
Mass is the amount of matter in an object and it does not change with location, which is what separates it from weight in physics. This converter works across twelve mass units, from micrograms used in pharmacology up to metric tonnes and the two different tons still in commercial use.
The awkward part of mass conversion is the ton. A metric tonne is 1000 kilograms, a US short ton is 2000 pounds or 907.18474 kilograms, and a UK long ton is 2240 pounds or 1016.0469088 kilograms. All three appear as separate options so a shipping document can be read without guessing. Grains and carats are included as well, since ammunition data and gemstone certificates still use them.
Values are converted one per line, which makes it quick to run through a column copied from a lab sheet. The pound factor of exactly 0.45359237 kilograms is the international avoirdupois pound agreed by every modern standards body. If your figures are really about how heavy something reads on a scale, the Weight Converter presents the same unit set with everyday defaults.
How to use
- Paste the mass values, one number per line.
- Select the unit you have and the unit you want.
- Read the converted values, the exact factor and the table.
- Copy or download the output.
Common questions
- What is the difference between mass and weight?
- Mass measures matter and stays the same anywhere. Weight is the force gravity applies to that mass, so it changes on the Moon. On Earth the everyday numbers are treated as interchangeable.
- Which ton does this tool use?
- All three are separate options: metric tonne, US short ton and UK long ton. Pick whichever is printed on your document.
- How many grams are in an ounce?
- An avoirdupois ounce is exactly 28.349523125 grams.
- What is a carat in grams?
- A metric carat is exactly 0.2 grams, so a five carat stone weighs one gram.