Convert weight units instantly between metric (kg, g, mg), imperial (lbs, oz, stones), and precious metals (carats, troy oz). Fast, accurate, and completely free weight conversion tool.
The international standard system based on powers of 10. Used worldwide for scientific and everyday measurements.
Traditional system used primarily in the United States and UK for everyday measurements.
Specialized units used for measuring precious metals, gems, and pharmaceuticals.
Our conversions use precise conversion factors and display up to 8 decimal places for maximum accuracy. Results are suitable for both everyday use and scientific applications.
Mass is the amount of matter in an object (measured in kg), while weight is the force of gravity on that mass (measured in Newtons). In everyday use, we often use "weight" to refer to mass.
The US ton (2000 lbs) and UK ton (2240 lbs) developed from different historical standards. The metric tonne (1000 kg) is part of the international system.
Troy ounces are used for precious metals like gold and silver. A troy ounce (31.1g) is heavier than a regular ounce (28.35g).
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