Print Volume & Fill Calculator

Slicer infill percentage is the fraction of the interior filled with plastic — not the percentage of total print time or weight. A 20% infill cube still has solid walls (perimeters) and top/bottom solid layers on top of the sparse interior.

This calculator estimates the bounding box volume and the infill portion only. Actual filament use includes walls, roofs, supports, and brim — always check your slicer estimate for job cost.

Example: a 100 × 100 × 50 mm box is 500 cm³ total. At 20% infill, the sparse interior holds about 100 cm³ of filament before walls and solid caps.

Infill percentage has strongly diminishing returns on strength. Published testing and community measurements consistently show the biggest gains between 0% and about 25%, after which added infill costs material and time far faster than it adds stiffness. Above roughly 50%, extra perimeters usually buy more strength than extra infill for the same grams.

Perimeter count often matters more than infill for the parts people actually break. Walls carry bending and tensile loads at the surface, so going from two to four perimeters typically stiffens a part more than doubling infill, and it does so with less material. Tune walls first, then raise infill only if the part still flexes.

The pattern changes behaviour at identical percentages. Gyroid is isotropic and prints without self-intersection, making it a good default; grid and cubic are stiffer in specific axes; lightning infill exists only to support top surfaces and adds almost no structural strength despite showing a percentage in the slicer.

A bounding box overestimates anything that is not a rectangular block, often by a wide margin — a sphere fills only about 52% of its bounding cube, and a typical mechanical part far less. Treat this figure as an upper bound and take the true mesh volume from your slicer when the number needs to be accurate.

Zero-infill prints still consume material, which surprises people modelling vases and shells. Solid top and bottom layers, the brim or skirt, and the perimeters themselves are all outside the infill calculation, so a hollow print's weight can be several times what an infill-only estimate suggests.

After estimating bounding-box infill volume here, use the filament weight calculator with your material density to translate cubic centimeters into grams on the spool.

Gyroid and cubic infill patterns use similar percentages but different strength — after estimating volume here, compare pattern choices in your slicer preview before committing filament.

Hollow vases with zero infill still use solid bottom and top layers — do not assume infill percentage equals total print weight.

Brim and skirt lines add a thin ring of extra material around the first layer — include them when comparing estimates to a finished weigh-in.