Infill Material Usage Calculator
The amount of plastic a 3D print uses depends heavily on its infill percentage. This calculator takes the model volume, the infill percentage, and the material density, and returns the solid plastic volume and the filament mass. The density is a user-editable input so you can switch between PLA, ABS, PETG and other materials. It is a quick estimate that treats the whole part as one infill fraction, so use your slicer for an exact figure.
Infill material formula
Solid plastic volume = model volume * (infill percent / 100)
Filament mass = solid plastic volume * density
Volume is in cubic centimetres and density in grams per cubic centimetre, so the mass comes out in grams. Common densities: PLA about 1.24, ABS about 1.04, PETG about 1.27 grams per cubic centimetre.
Worked example
A 50 cm cubed model at 20 percent infill in PLA (density 1.24): solid plastic volume = 50 * 0.20 = 10.00 cm cubed. Filament mass = 10 * 1.24 = 12.40 g.
Infill material: frequently asked questions
How does infill percentage affect material use?
Infill percentage is the fraction of the interior that is filled with plastic rather than left hollow. A model's solid plastic volume is roughly its total volume times the infill fraction. At 100 percent infill the part is solid; at 20 percent only a fifth of the interior is plastic, so it uses far less filament.
How is filament mass found from volume?
Multiply the solid plastic volume in cubic centimetres by the material density in grams per cubic centimetre. PLA is about 1.24 g per cubic centimetre and ABS about 1.04, so the density is a user-editable input. Mass equals volume times density.
Why is this only an estimate?
Real prints add perimeters (walls), top and bottom solid layers, and supports, which this simple model approximates by treating the whole part as one infill fraction. For an exact figure, use your slicer, which reports filament length and weight after slicing.
Official sources
- U.S. National Institute of Standards and Technology: Additive Manufacturing.
- The mass relationship follows from the definition of density as mass divided by volume.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.