Area Density Calculator
Works out how much something weighs per unit of area, such as paper, fabric, roofing, or a crop on the ground.
Kilograms per square metre
— kg/m²
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Grams per square metre — g/m²
Pounds per square foot — lb/ft²
Ounces per square yard — oz/yd²
Tonnes per hectare — t/ha
The formula
area density = mass ÷ area
Also called areal density or, for paper and fabric, grammage. For a uniform sheet it equals the bulk density times the thickness.
What to watch out for
Measure a sample of known size, weigh it, and enter both. A larger sample evens out any variation.
Frequently Asked Questions
What is the difference between area density and density?
Density is mass per volume. Area density is mass per area, which is the useful figure when thickness is fixed or does not matter.
How do I convert kg/m² to lb/ft²?
Multiply by 0.2048. So 12 kg over 8 m² is 1.50 kg/m², or 0.307 lb/ft².