Deflection Calculator (TM)

Our deflection calculator makes it easy to calculate stylus deflection.


Simply enter the shaft diameter, wall thickness (if tube), and free shaft length.  Enter the probing force in grams, newtons, or ounces, and then select the shaft material from the drop-down box.  Click on "Calculate" for the result.


The published probing forces for several Zeiss and Renishaw CMM probe heads are listed below.  If you know which probe head you're using, just click on it to enter the minimum force value.  If you're unsure of the force of your probing system, it's best to check with the manufacturer.

Stem/Shaft Diameter


Wall Thickness mm in
Free Length Of Stem/Shaft mm in
Probing Force lbs
Stem/Shaft Material PSI


Standard probe head forces



XXT: 0.01 to 0.13 N, depending on stylus length. TP20 Standard Module: 0.08 N TP200: 0.02 N
DT: Selectable, 0.05 to 1.0 N TP20 Low Module: 0.055 N TP6/TP6A: 0.11 to 0.3 N
VAST XT Gold: Selectable, 0.05 to 1.0 N TP20 Medium Module: 0.1 N TP7M: 0.02 N
VAST Gold: Selectable, 0.05 to 1.0 N TP20 Extended Module: 0.1 N TP2: 0.07 to 0.15 N
Click on your probe head to set force.