Infill Percentage Guide

Infill is a strength-vs-time-and-material tradeoff, not a single "correct" number — here's what each range is actually for.

InfillRelative strengthMaterial & time costTypical use
0–5%Very lowMinimalDisplay models, prototypes never handled under load
10–15%Light dutyLowStandard default for most non-structural prints
20–30%ModerateModerateFunctional parts, brackets, light mechanical use
40–60%HighHighLoad-bearing parts, parts that will be drilled or tapped
80–100%MaximumVery highSmall high-stress parts where the added time/material is worth it

Pattern matters almost as much as percentage

Gyroid infill is a common default because it's strong in every direction and prints reasonably fast; grid and lines patterns are faster still but weaker along one axis; honeycomb and cubic patterns trade print speed for more even multi-directional strength. If a part keeps failing along one particular plane, switching pattern can matter more than just raising the percentage.

Perimeters do more than infill thinks

For parts under bending stress rather than crushing stress, adding perimeter (wall) count usually adds more real-world strength per minute of extra print time than raising infill percentage does — the outer walls carry most of the load in a lot of everyday functional prints. If a part snaps at the surface rather than crushing internally, try more perimeters before reaching for higher infill.

Related Calculators