Shrinkage compensation calculator
Print a calibration piece, measure it, and get the exact scale % for your slicer. Dial in extrusion first with the rotation distance calculator — over-extrusion fakes shrinkage — then check the max print speed for your material.
Measure above the first few layers — elephant's foot and first-layer squish skew measurements taken near the bed.
100.000%
new slicer scale, axis 1 — PrusaSlicer / Cura convention
check calibration outside the typical ABS/ASA window — check rotation distance/first layer before scaling
| Shrinkage, axis 1 | – |
| Bambu Studio / OrcaSlicer “Shrinkage”, axis 1 | – |
| New scale, axis 2 | – |
| Shrinkage, axis 2 | – |
| Bambu Studio / OrcaSlicer “Shrinkage”, axis 2 | – |
| Typical shrink, ABS / ASA | – |
| Reverse: will print at | – |
How it works
The correction is a ratio: new scale = current scale × (designed ÷ measured). A part designed at 50 mm that measures 49.55 mm needs 100 × 50 ÷ 49.55 ≈ 100.91%. Corrections compound — they multiply, they do not add: if you apply two successive corrections, the total scale is their product (a common forum mistake is adding the percentages, which drifts further off each iteration). Most ABS/ASA filaments land in a 0.995–1.005 shrink factor (99.5–100.5% scale) window; far outside that, suspect over-extrusion, wet filament or a cooling problem rather than pure shrinkage. Reverse mode answers “at this scale %, what size will my part actually print?”
Mind the convention: PrusaSlicer and Cura take a scale % (designed ÷ measured), while Bambu Studio and OrcaSlicer take a filament “Shrinkage” % (measured ÷ designed — they invert it internally). The same 50 → 49.55 mm part is 100.91% scale in PrusaSlicer but 99.10% shrinkage in Bambu Studio; entering one where the other belongs doubles the error instead of fixing it. The breakdown shows both, labelled.
Frequently asked questions
How much does ABS shrink when it cools?
Most ABS and ASA parts land within half a percent — a correct compensation scale is usually between 99.5% and 100.5%. Far outside that window, suspect over-extrusion, wet filament or a cooling problem rather than pure shrinkage.
Should I add successive shrinkage corrections together?
No — corrections compound by multiplying. Applying a 100.91% correction on top of an existing 101% scale gives 101 × 1.0091 ≈ 101.92%, not 101.91%. The calculator multiplies your current scale automatically.
Why is my part still the wrong size after scaling?
Scale fixes uniform thermal shrink only. Elephant foot, first-layer squish and over-extrusion change dimensions differently, so calibrate rotation distance first and measure above the first few layers.
Does shrinkage compensation apply to the Z axis?
No — Z height is set by discrete layer steps, not by cooling shrink. Measure and compensate X and Y; consistent Z errors usually point at first-layer or extrusion issues instead.