Parts of a Vernier Caliper

Vernier Scale

The Vernier scale consists of a measurement of 49 mm marked in millimeters. It is used to determine the second decimal number in millimeter reading.

Ears/Upper Jaw

This is used to measure the internal diameter of objects.

Lower Jaw

This is used to measure the external diameter of a tube or container.

Main Scale

This is used to determine the main length of the materials.


This gauges the least count, the smallest increments in the readings of a measuring instrument. A Vernier caliper is an apparatus used to accurately measure length. This measurement is important in determining the density of solids, which can be directly gauged by their mass and volume. The Vernier caliper has five main parts: the Vernier scale, the ears/upper jaw, the lower jaw, the main scale and the tail.