Mass Calculator
Calculate mass from density and volume, or from force and acceleration.
About Mass Calculator
Mass can be derived two ways: from its definition as density × volume (useful for objects of known material), or from Newton's second law F = ma (useful when you know the net force and resulting acceleration). Note that mass and weight are different quantities — mass is a measure of inertia, weight is the gravitational force on that mass.
Formulas
Mass from density and volume
Mass = Density × Volume
- m
- Mass (kg)
- ρ
- Density (kg/m³)
- V
- Volume (m³)
Mass from Newton's second law
Mass = Net Force ÷ Acceleration
- m
- Mass (kg)
- F
- Net force (N)
- a
- Acceleration (m/s²)
Worked example
With the default values below, Mass Calculator returns Mass of 1,000.000000. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Methodone of m = ρ × V (density × volume), m = F / a (Newton's 2nd law)
- m = ρ × V (density × volume)
- Density (ρ)minimum 0
- 1,000
- Density Unitone of kg/m³, g/cm³, g/L, kg/L, lb/ft³
- kg/m³
- Volume (V)minimum 0
- 1
- Volume Unitone of m³, cm³, L, mL, ft³, in³, gal
- m³
- Net Force (F)minimum 0
- 100
- Force Unitone of N, kN, lbf, kgf, dyn
- N
- Acceleration (a)minimum 0
- 9.80665
- Acceleration Unitone of m/s², ft/s², g, cm/s²
- m/s²
- Output Mass Unitone of kg, g, mg, lb, oz, t, slug
- kg
Results
- Mass
- 1,000.000000
- Mass (kg)
- 1,000.000000
- Mass (lb)
- 2,204.624
- Mass (g)
- 1,000,000.000
Step by step
- 1Density in kg/m³= 1000 kg/m³
- 2Volume in m³= 1 m³
- 3Mass = density × volume= 1000 kg = 1000 kg
Assumptions and limits
- The result is derived only from the 10 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 6 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
What is the difference between mass and weight?
Mass is the amount of matter in an object (kilograms) and does not change with location. Weight is the force exerted by gravity on that mass (Newtons): W = mg. On the Moon, your mass is the same but your weight is 1/6 that on Earth.
When would I use m = F/a instead of m = ρV?
Use F/a when you measure the force applied to an object and its resulting acceleration — for example, when calibrating a force sensor or solving a physics problem. Use ρV when you know the material and can measure the object's volume.
What is a slug?
A slug is the US customary unit of mass: the mass that accelerates at 1 ft/s² under 1 lbf of force. 1 slug = 14.594 kg. It's rarely used outside engineering dynamics.
1 litre of water weighs how many kg?
Water's density is 1 kg/L at standard conditions, so 1 litre of water has a mass of 1 kg. Enter density=1 kg/L, volume=1 L to verify.