How to Measure a Chainsaw Bar Length: Getting the Correct Measurement

how to measure a chainsaw bar length

The first thing to do when changing the chainsaw chain is to know how to measure a chainsaw bar length.

Whether you need to replace the bar or chain or want to know the cutting capacity of your chainsaw, it is a process you can do yourself, without having to ask an expert.


Difference Between Bar Length and Cutting Length

When considering the size of the bar, we need to take into account two dimensions:

  1. Bar length
  2. Cutting length

The cutting length, or cutting capacity, will necessarily be a few inches shorter than the overall length of the bar.

bar length and cutting length

Getting the Correct Measurement

If you can measure the length of the chainsaw bar by yourself, you will avoid wasting time going to the local shop, and you will be able to buy the new bar online, saving you time and money.

To do this, the only condition is that you must accurately specify the length of the bar, so you can be sure that you are ordering the right one. That is why this question rises on how to measure a chainsaw bar length.

In this information, you are going to learn more about this and other frequently asked questions.

How To Measure Bar On Chainsaw

Quick note: depending on the manufacturer, you will find the bar length on one of the sides of the bar.

You may have the right size right away without opening the saw case.

However, due to wear, it is sometimes difficult to read this information on the bar.

To measure the length of the bar, you need to remove the screws or the fixing mechanisms of the chainsaw case.

Once you open the case, you will have the bar exposed. With a measuring tape, you can now measure the entire length from one end to the other.

This measurement will be showing the actual size of the chainsaw bar.

The most common sizes of a chainsaw bar range between 8 and 20.

Three More Numbers to Check

When it comes to replacing chainsaw bars, three other numbers need to be correct to make sure the new bar fits your chain perfectly.

  1. Chain length
  2. Pitch
  3. Gauge

1. Chain length

To measure the chain length, you need to count the number of links. The mesh sizes are standard for all brands.

If the links in your chain are 84, as in the example in the following figure, then the bar should have this number in the specification box. Usually, this value is engraved on the same bar, or in any case, must be considered at the time of purchase.

chain length

2. Pitch

The pitch is a measurement also indicated on the bar and is the distance between the rivets of the chain.

If our example, the pitch of the chain is 3/8".


3. Gauge

The gauge is the width of the groove along the outer perimeter of the bar, which must correspond to the width of the chain link.

bar groove

Here's how to find the gauge rating, as shown in the image below. In our case, the number is 0.050".


Once you have verified these three numbers, chain length, pitch, and gauge, together with the bar length, these are the measurements you need to keep in mind when you are buying a new bar.

Unfortunately, after many years of use, the box information on your bar may be very hard to read. Other bars will not be having these numbers stamped.

All these data must be correct, so to be sure that your chain fits the new bar correctly.

When Should I Replace the Chainsaw Bar?

A chainsaw bar has to withstand very severe stresses. The chain, first of all, rotates around it at high speed, and while cutting, it must endure strong vibrations, twists, and tensions.

Therefore, it is necessary to know how to recognize the signs and damages that will tell us when to replace it.

In the following video, we can learn a lot about the wear and tear that a chainsaw bar undergoes.

Video: When A Chainsaw Bar Needs To Be Replaced!

Types of Chainsaw Bars Explained

There are many types of chainsaw bars on the market, and they are designed to perform specific tasks, with some advantages and disadvantages.

Below we will mention the most common ones.

Solid bars

Solid bars are designed to cut hardwood, thick bark logs in very dusty conditions. These are steel bars resistant to scratches and corrosion.

Some types of solid bars have replaceable noses because it is the part that wears faster.

The drawback of these bars is that they are more expensive and tend to become very hot, dispersing part of the power developed by the saw motor.

Sprocket nose bars

Bars with a sprocket nose allow the chain to spin faster thanks to reduced friction, with less heat and less power loss.

Replaceable sprocket nose bars

These types of bars are among the most common, and if the pinion breaks, the advantage is that you don't have to replace the whole bar, which is much more convenient. They are a little more expensive.


What is the best length for a chainsaw bar?

A bar between 14 and 18 inches in length should be suitable for everyday uses such as:

  1. Cut small to medium-sized branches.
  2. Cut wood for the fireplace
  3. General maintenance of your backyard

This bar size will not be suitable for the most difficult tasks, but it is ideal for home use.

Are chainsaw bars universal?

No. With a few exceptions, it is not possible to use a bar from one brand on a chainsaw from another brand.

Why is my chainsaw not cutting straight?

When the chainsaw starts pulling on one side, it is a sign that it needs blade maintenance, although it could also be a warning of a more severe problem.


Chainsaws are dangerous and complex tools. With proper precautions, safety, knowledge, and gear, you will be capable of ensuring a job is done without any problems.

Hence, it is crucial to keep all parts in good condition.

When the time comes to replace the bar or chain, it is crucial to know how to measure them.

If you are a serious professional or even a hobbyist, learning this easy process will help you learn more about the functionality of your equipment.