All-in-one unit conversion tool
Unit converters typically handle length, weight, volume, temperature, area, speed, time, energy, pressure, and data storage. Our converter supports all major metric and imperial units across these categories.
The metric system (SI) was developed in France for scientific precision and decimal simplicity. Imperial/US customary units evolved from historical British measurements. Most countries use metric; US, Myanmar, and Liberia primarily use imperial.
Common conversions: 1 inch = 2.54 cm, 1 mile = 1.609 km, 1 lb = 0.454 kg, 1 gallon = 3.785 L. For quick mental math, multiply km by 0.6 for miles, or kg by 2.2 for pounds.
Mass is the amount of matter (measured in kg), constant everywhere. Weight is the gravitational force on that mass, varying by location. On Earth, we use them interchangeably, but on the Moon, your weight would be 1/6th of Earth.
Historical regional variations created confusion—US gallon (3.785L) vs UK gallon (4.546L), short ton (2000 lbs) vs metric ton (1000 kg). Always verify which system is being used, especially in international contexts.
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