Best 7 Types of Vernier Caliper

Vernier caliper is a linear measuring instrument. We can measure a small object. Every mechanical student and employee should know about this. In this article, I explain full details about it. Before discussing all vernier first know what is Vernier ?

Vernier Caliper:

Vernier Caliper

The word vernier means any instrument with two jaws. It is used to specify the diameters of objects. In 1631 French scientist Pierre vernier introduced vernier caliper to accurate measurements.

The vernier is a measuring instrument. It is used to measure linear dimensions. It did not need the object is related to the mechanical manufacture object.

The vernier consists of a main scale. It has a fixed jaw. It also has a sliding jaw. The jaws are attached to the vernier main scale. The vernier caliper is capable to measure internal diameter and external diameter. This type of measurement is not possible with a meter scale.

Also Read : Best 9 Measuring Instrument for Mechanical sector

Types of Vernier Caliper:

There are some types of vernier caliper given below:

  • Flat edge vernier caliper
  • Knife-edge vernier caliper
  • Vernier gear tooth caliper
  • Vernier depth gauge
  • Flat and knife-edge Vernier caliper
  • Vernier height gauge
  • Vernier dial caliper

Flat Edge Vernier Caliper:

Flat edge Vernier caliper is the type of Vernier which is used for normal functions. By using we measure length, breadth, thickness, and diameter. Through its edge, we measure the inner measurements of an object.

Knife Edge Vernier Caliper:

Knife-edge Vernier caliper is the type of Vernier which have the same edges as a knife. It is used to measure narrow spaces area. Due to the thin edge, it is important. If we wear out quickly and we found an inaccurate measurement. So this type of vernier is used carefully.

Flat And Knife Edge Vernier Caliper:

Flat and knife-edge vernier caliper is a type of vernier. Where its jaw is like an ordinary vernier caliper. Here it’s knife-edge jaw at the other side. This vernier can be used to measure all types of objects. It is eligible to measure everything easily.

Vernier Gear Tooth Caliper:

Vernier gear tooth caliper is a special type of vernier. It is manufactured from a joint form of two Vernier calipers. This Vernier consists of two separate scales. The first one is the vertical scale and the other is the horizontal scale. By this Vernier , we take a tooth of gear from the pitch circle. This type of Vernier is used to measure various parts of the gear.

Vernier Depth Gauge:.

Vernier depth gauge is an instrument. It is used to measure the depth of the slot of any particular object. The slot is like a hole or groove. This type of Vernier reading process is the same as others. The main and Vernier scale is also found in either inch or metric systems.

Vernier Height Gauge:

Vernier Caliper
Image Credit – Glenn McKechnie

Vernier height gauges are used to measure the height of an object. These types of instruments are quite like to the other Vernier caliper. Where some attachments are used.

Vernier Dial Caliper:

Vernier Caliper

In dial vernier caliper we found accurate measurement. Nowadays dial vernier is used in everywhere for reading. In simple vernier, we found some error so it is now used.

It is like to simple vernier. With this equipment, we measure the dimensions in inches and mm. A rack and pinion are used in this type of vernier. The rack is fit on the main scale. It is connected to the pinion of the dial.

Parts of Vernier Caliper:

Vernier Caliper
Image Credit – Lucasbosch

The main components of the vernier caliper are the

Main Scale:

It is a big scale of the vernier. It rides also the body of the vernier. The reading on the main scale is I’m, mm, and inch. According to the is units 1 mm is the lowest main scale, division.

Vernier Scale:

This is the smaller scale of the vernier. It is attached to the main scale. Its actions along the main scale. The movement of the vernier scale depends on the jaws opening. The purpose of the vernier scale is to provide accuracy to the main scale reading. It is held by dividing the reading into smaller increments. The vernier scale has divisions up to 50. It’s every division measures 0.02 mm.

Lower Jaws:

These jaws are assumed to be one of the most well-known features of vernier caliper. Its one jaw is fixed and attached to the main scale. Its other jaw is movable. It is attached to the vernier scale. These jaws are constructed to grip the objects firmly. The function of the lower jaw is to measure the outer dimensions. Such as diameter, width, and length.

Upper Jaws:

These jaws are the same as the lower jaws. But it is smaller than the lower jaws. It is attached to the upper part of the vernier scale. It’s one of the jaws is fixed and the other jaw is movable. The purpose of the upper jaw is to measure the inner dimensions of objects. Before taking the reading the jaw is opened till they touch the edges. We can measure hollow pipes inside diameter using upper jaws.

Depth Rod:

The depth of the object can be measured using the depth rod. It is a thin rod. It is fixed at the end of the main scale. The edge of the main scale is set on the top surface of the object. Then the jaws are slowly opened. The opening of the jaws shows the depth length.

Thumb Screw:

This thumbscrew is found at the bottom of the vernier scale. The main purpose of the thumbscrew is to provide grip to the users. So the sliding of the jaws comes to be easy.

Lock Screw:

The use of the lock screw is to fix the position of the jaws. This is easy to carry proper readings.

Vernier Caliper Least Count:

The difference between one main scale division and one vernier scale division is known as Least count.

Least Count= 1M.S.D – 1VSD

                     =(1mm – 49/50)mm

                     =1/50= 2/100(multiply×2) = 0.02mm

The least count of vernier caliper is the small value. We can measure from this device.

Calculate Vernier scale Reading:

Follow this formula: M.S.R+(V.C×L.C)

M.S.R = Main scale division

V.C = Vernier scale division

L.C = Least Count

How To Read Vernier Caliper?

Vernier Caliper
Image Credit – Simon A. Eugster
  • At first check the main scale and vernier scale aligned with each other. This is the first step.
  • Do the main scale 0 points and the vernier scale 0 points at the same line. It means the vernier is no zero error.
  • After that place the object between the two jaws of the vernier scale.
  • Then take a look at the 0 mark on the vernier scale lining with the main scale.
  • It provides the main scale reading.
  • Then show the point on the vernier scale which is aligned with the main scale. It provides the vernier scale reading.
  • It is crucial to note that the readings most of the time be in decimals.
  • The point before the decimal point is the main scale reading. The point after the decimal point is the vernier scale reading.

How to read the depth using a Vernier Caliper?

Vernier Caliper
Image Credit – Peter Southwood

There are some steps for measuring depth with a vernier caliper:

  • Set the edge of the main scale on the beaker.
  • Rotate the thumbscrew. Rotate it till the tip of the depth rod touches the bottom of the beaker.
  • Then tighten the lock screw.
  • Then show the readings.

What is Zero Error?

If the 0 points of the main scale and the zero point of the vernier scale are not placed in the same line. Then it is called zero error.

Zero error of vernier caliper is estimated as:

Reading = M.S.D + V.S.D– (Z.E)


M.S.D = Main scale division

V.S.D =Vernier scale division

Z.E = Zero error

Precautions for taking Vernier Caliper reading:

  • we can’t slide the vernier over the main scale vigorously. it can be moved smoothly over the main scale.
  • Whose dimension should be measured is hold between the jaw. The object will be a  spherical ball and cylinder.
  • The zero error of depth is different from other zero errors so it is specified separately.

The Principle of Vernier Caliper:

A scale does not measure an object which is smaller than 1 mm. But vernier can measure it. I already explain the vernier caller has two scales. By these two scales, we can measure length like 0.1mm.

Here the two-scale reading is 1 mm and 0.9 mm. So 10 division of the main scale is 1 cm. So 10 division of the vernier scale is 0.9mm. The difference between the main scale and the vernier scale is 0 1mm. It is the working principle of the vernier.

Uses of Vernier Caliper:

We know the Vernier Calipers is used to measure the distance. We measure the internal and external dimensions. We can measure the height of an object with perfect accuracy. We can measure up to hundreds of mm.

Vernier use in

  • Science Labs
  • Medical Purposes
  • Steel Industries
  • Aerospace Industries
  • Educational Sector

Science Labs

One of the important use of this instrument is in this area. It is used for study materials. It is used to measure various equipment. They are also useful for measurements of regular and irregular-shaped objects.

Medical Purposes

The medical and surgical enterprise depends on this equipment extensively. Because the dimensions of instruments have been measured for surgery.

Steel Industries

To check and manufacture the dimensions of a product we use vernier. It is used to measure the width and height of various objects. It also measures holes, the width of the pipe, and the circumference of metal beads.

Educational Sector

The vernier caliper is used in schools and engineering institutions. These instruments help students for study. The vernier is used to measure the outside and inside diameters.

Advantages of Vernier Caliper:

Two advantages of vernier caliper:

  • The measurements given by the vernier are accurate and precise.
  • It is eligible for measuring both inner surface and outer surface dimensions.

Limitations of Vernier Caliper:

Limitations are:

  • The inappropriate angle of vision is not wrong reading.
  • The least attentiveness leads to the recording of the bad reading.


In this article, I explain about vernier caliper. Vernier is used as per need in some types. I explain its types in this article. This vernier article is used fully for students and the mechanical sector.

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