حاسبة الكتلة
The detailed guide below is currently available in English.
Mass from density and volume
Density states how many grams each cubic centimeter of a material weighs, so multiplying it by the volume gives the total mass: m = ρV. The worked default — water at 1 g/cm³ filling a 1,000 cm³ (one liter) bottle — lands on exactly 1 kilogram, a useful anchor. Metals run far higher (steel about 7.85 g/cm³), while gases are thousands of times thinner than liquids.
Mass versus weight
Mass measures the quantity of matter and never changes with location. Weight measures the force gravity exerts on that mass, so a astronaut weighs a sixth as much on the Moon while their mass is untouched. Converting between the two needs gravity (weight = mass × g), which is what the weight calculator does; this page sticks to mass in grams, kilograms, and pounds — the pound here being the pound-mass used in commerce.
الأسئلة الشائعة
Are pounds here mass or force?
This calculator treats the pound as a unit of mass (pound-mass, lb), the sense used on grocery scales and in shipping. The force sense, pound-force, appears on the weight calculator instead, where gravity enters the picture.
How accurate is the water density of 1 g/cm³?
Very close for everyday work. Water peaks near 0.99997 g/cm³ at about 4 °C and drops slightly as it warms, but for household and classroom calculations 1 g/cm³ (1 kg/L) is the standard shortcut.