Determine the force due to weight: (W = m g)
Rearrange the formula to solve for mass: (m = frac{W}{g})
Use (g approx 9.81 , text{m/s}^2) on Earth
Divide the weight in newtons by (9.81) to get mass in kilograms
Use the local gravitational acceleration if not on Earth
Ensure the weight is measured in force units, not mass units
Convert units first if weight is given in pounds-force or other units
Apply the same formula with consistent units throughout