Mass Unit Conversion Calculator

What is mass and how do measure it?

In physics, mass is a measure of an object’s inertia – the resistance of an object to a change in its speed when a force is applied to it. This definition may seem foreign to our intuitive understanding of mass, because we generally associate mass with weight.

Mass and weight are related but distinctly separate phenomena. Where mass is completely independent of its location, weight is a force dependent on both mass and gravity (i.e. Weight = Mass × Gravity). These terms are often incorrectly used interchangeably because on the surface of earth the gravity we experience is almost the same everywhere. Therefore, weight and mass seem to be directly proportional to each other.

For a more information on mass, inertia and weight, see

Use our free online mass unit conversion calculator to easily convert between units of mass including grams (g), kilograms (kg), metric tonnes (tonne), short tons (shton), long tons (Lton), pounds (lb) and ounces (oz).

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Please note that this or any other calculators on the tools room are for information only. WKC Group has endeavoured to ensure that the information presented here is accurate and that the calculations are correct, but will not accept responsibility for any consequential damages, faults or human errors that may arise from the use of formulas, inventories and values.