The Easy Java Simulations Modeling and Authoring Tool is needed to explore the computational model used in the Vernier Caliper Model.

The Vernier Calipers model was created by created by Fu-Kwun Hwang for the NTNU website and later customized by Loo Kang Wee and Wolfgang Christian for the OSP Collection.

The original source codes for the base Vernier Caliper Model by Fu-Kwun Hwang.

The source codes for the blue and green objects in Vernier Caliper Model by Fu-Kwun Hwang.

The non Ejs version of the Vernier Caliper Model by Fu-Kwun Hwang that has the input field for student checking their understanding especially useful for learning the importance of precision of measurement.
This is because 19.40 is precise, 19.450 is too precise and 19.4 is not precise enough for the vernier caliper of smallest unit 0.01 mm.