0.2 to 0.6%. Across 100 mm that is a finished dimension anywhere from 99.8 to 99.4 mm.
The headline figure sits between PLA and ABS, as you would expect. The awkward part is the width of the band rather than its position.
A wide band means an unpredictable part
PLA's range spans three tenths of a percent; PETG's spans four, and PETG is printed across a wider useful temperature window than PLA is. Nozzle temperature, bed temperature and part cooling all move where within the band a given print lands.
The practical consequence: two PETG parts from the same spool, printed at 230 °C and 250 °C, will not measure the same. If you are compensating, compensate for your profile, not for the material — and recompensate if you change the temperature.
Compensation figures
Model a 100 mm dimension at 100.2004 mm at the low end of the band, or 100.6036 mm at the high end. Corrections of 0.2004 and 0.6036 mm.
Guessing the midpoint of a band that wide is not much better than not compensating at all. Print one calibration part, measure it, and derive the factor from the result.
Where PETG's dimensional behaviour actually bites
Holes, and specifically holes for fasteners. PETG stays soft longer than PLA after deposition, so an internal circle sags inward slightly beyond what shrinkage alone predicts. A hole modelled at nominal will usually come out tight.
That effect is separate from linear contraction, it does not scale with the part, and no global scale factor fixes it — the fix is to model the hole oversize.
The filled grade is far more stable
PETG-CF contracts only 0.1 to 0.4%, less than half the band and less than plain PLA at the top end. The chopped fibre restrains the polymer as it cools and narrows the spread at the same time.
For a large PETG part that has to be dimensionally right, the filled version is a genuine engineering answer rather than a marketing one.
Enter the contraction you measured on your own profile into the shrinkage calculator rather than a figure from a table. PETG's stored band sits alongside its temperatures on the PETG page.