Weight Converter

Weight and mass units get confusing fast once you leave plain kilograms and pounds, because several different measurement systems overlap without lining up: avoirdupois ounces and pounds (the everyday kind, used for groceries and body weight) are not the same as troy ounces (used for precious metals) or apothecary weights, a US "ton" is 2,000 pounds while a UK "ton" is 2,240, and grains, drams, and stone all still show up in recipes, old records, and specific trades without much explanation of what they actually equal. This converter keeps all of them straight — 27 units in total, spanning metric, avoirdupois, troy, and a few scientific units like the atomic mass unit — so you don't have to remember which system a given unit belongs to before converting it.

Enter a value in either field and the other calculates instantly; the swap control reverses the two units if needed. Every conversion routes through grams as a common reference point, verified against known values — a US short ton correctly comes out to 907.18474 kg here, distinct from the UK long ton's 1,016.05 kg, rather than the two being quietly treated as interchangeable.

Dedicated pages for the most commonly looked-up pairs — kilograms to pounds, grams to ounces, kilograms to stone — are linked below with preloaded calculators and quick-reference tables. As with every tool on this site, the conversion happens entirely in your browser with no external lookup and nothing recorded.