Weight Calculator (W = mg)

This calculator works out weight, mass or gravitational field strength using the physics formula W equals mg, where W is weight in newtons, m is mass in kilograms and g is gravity in metres per second squared. Weight and mass are not the same thing: mass is a fixed amount of matter, while weight is the force gravity exerts on it, so the same object weighs differently depending on where it is. You choose which of the three values to solve for from the dropdown, then enter the other two into the Weight, Mass and Gravity fields. The calculator instantly returns the solved value with a labelled result showing which variable it worked out, updating live as you change any input. The gravity field defaults to Earth's standard 9.81 metres per second squared, but you can overwrite it with about 1.62 for the Moon or 3.71 for Mars, which makes the tool handy for comparing how the same mass behaves in different gravitational environments. It suits physics students checking homework, teachers preparing worked examples, and engineers who need a quick, reliable conversion between mass and weight. Results are rounded for display, so treat them as an exact calculation of the formula entered rather than a physical measurement, and always check that your inputs match the kilograms, newtons and metres per second squared units as labelled.

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