3D Print Shrinkage Calculator

Multiply each desired dimension by (1 + shrinkage / 100). For PLA at the typical 0.4% shrinkage, a 100mm cube needs to print at 100.4mm. For ABS at 0.75%, the same cube prints at 100.75mm. Nylon at 1.75% means 100mm becomes 101.75mm. Resin sits in the wide range of 1.0% to 2.5% depending on chemistry, with 1.5% as a practical default. The calculator above bakes these typical values in and applies the multiplier per axis.

The reason it matters is that shrinkage isn't optional - it happens whether you compensate or not. If you print a part designed for a 4mm hole at PLA's 0.4% shrinkage, your real hole will measure 3.984mm; you'll struggle to fit a 4mm dowel into it. Compensate up-front and the dowel slides in cleanly. The catch is that shrinkage is rarely uniform across X, Y and Z, so many serious users measure a calibration cube on their own printer and feed the actual percentages in rather than trusting the typical figure.

X and Y (the horizontal axes) usually shrink uniformly because each layer cools quickly while pressed against the bed and the layer below. Z (the vertical axis) often shrinks less, because each layer is laid down at extrusion temperature on top of an already-cooled layer, so the cooling distance is shorter. ABS in particular shows pronounced X-Y shrinkage from the heated bed cooling unevenly across the perimeter, with the corners curling first.

The practical implication: a single shrinkage value works for cubes and simple prints, but for a part where the Z dimension matters (a stacked tolerance, a sliding fit), measure Z separately. The calculator lets you set X, Y and Z dimensions independently, so once you've measured a calibration print on your specific filament and machine you can plug in three different percentages. For a deeper cost analysis on filament use, pair this with the [3D print cost calculator](/3d-print-cost-calculator).

PLA from Brand A and PLA from Brand B can shrink differently. The polymer is the same in name, but additives, dyes and the supplier's drying regime change the cooling behaviour. The values in this calculator (PLA 0.4%, ABS 0.75%, PETG 0.45%, Nylon 1.75%, ASA 0.7%, Resin 1.5%) are typical mid-range figures that match published datasheets and the consensus on the RepRap and 3D printing forums. They are starting points, not guarantees.

If you're doing dimensional work - parts that fit other parts, threaded inserts, push-fits, gears - print a calibration cube in your specific filament, measure it cold (24 hours after printing for ABS, since it keeps shrinking), and dial the calculator's custom shrinkage percentage to match. Spend an hour calibrating once and you save weeks of failed prints. For a comparison table of common filaments by warp and shrinkage behaviour, see the [filament comparison](/filament-comparison) tool.

FDM filaments shrink as the molten plastic cools to room temperature. Resin shrinks during cure, when liquid polymer becomes solid through UV exposure. The numbers look similar (1.0% to 2.5% typical), but the failure modes are different. Resin shrinkage is anisotropic, meaning it's stronger in the direction of layer-build (Z), and it depends heavily on how thoroughly the part is cured.

Under-curing leaves residual monomer that keeps shrinking for hours after wash. Over-curing makes the part brittle but more dimensionally stable. The shop trick: cure resin parts overnight with the door of the wash-and-cure station closed, then measure 24 hours later. Apply the resin shrinkage value to all three axes equally as a first pass, but expect Z to shrink slightly more than X and Y. For high-precision parts, scale up by 1.5% then sand to final size; for cosplay and decorative work, the typical 1.5% bake-in is accurate enough.