How to Measure a Chainsaw Bar?

The body of a chain saw holds the engine or motor, the parts that run the saw. However, we cannot fail to underscore the bar and chain which are the parts that perform the actual cutting. Each chain saw has its corresponding bar and chain.

How to Measure a Chainsaw Bar

Larger and more powerful saws use longer bars; they are commonly used for heavy-duty tasks. They need more energy to run the chain around the long bar. The smaller and less powerful chain saws need shorter bars since they are used for low duty work.

The same case applies to chain saw chains; they are measured to fit corresponding bars. The chain should not be too narrow or wide for the bar because this will loosen the tension required to drive the chain saw. Therefore the chain has to fit perfectly on the bar. When choosing a replacement bar or chain, you might need to refer to the manual. However, if you have misplaced or trashed it, no need to stress about it. You can be able to learn how to measure a chain saw bar and chain, then you will get the appropriate replacement parts for the saw.

 Basically, the size of your best chainsaw bar for saws that are small to medium will range from 12 inches to 20 inches. Larger saws will star from 20 inches upwards. In this guide, we will teach you how to take bar and chain measurements and features you need to know about them.

How to measure the chain saw bar –

Measuring the length of the chain saw bar is not as easy as extending your tape measure from one end to the other. At the same time it’s not that difficult; exactly why you are doing it yourself. The chain saw bar length means the entire cutting length, which is the top and bottom of the bar. For now, we will give you the steps to follow when measuring the bar length.

  • Safety comes first before everything else; your life has to be protected. To ensure this, turn off the chain saw by removing the plug wire from the power source.
  • Lay the chain saw on a sturdy surface so that it will not fall off and injure you. The place needs to be flat for the chain saw to stay upright.
  • To find the cutting length of the chain saw bar, extend your tape measure from the tip of the saw blade. Measure the region of the chain saw where the bar protrudes from the outer casing of the saw.
  • Always round your findings to the nearest whole inch after measuring the bar length; you can find accurate readings. Any fraction greater than a half will round up to the next inch but any fraction less than a half is insignificant.
  • You need to keep in mind that the measurement attained is not the overall bar length; it is only part of the bar length.

There are two strategies used to measure the length of the bar. You can measure the effective length or the true length; they differ in inches.

Effective length.

This is also known as the cutting length and is the easiest to measure. This is the size of the bar that is exposed from the casing. It pretty much does the actual cutting and is shorter than the actual bar length.

True length.

This is the overall chain saw bar length. To obtain this measurement, you will have to use a wrench set or socket driver to remove the screws tightening the cover on the chain saw.

Remove the whole outer casing to expose the entire chain saw bar. The bar will be left loosely lying across the chain saw the body. Lift the bar and lay it down flat.

The measuring part will be easy you just place the end of the tape measure on one end of the bar. Extend the tape measure to the other and of the bar and record the measurement. You will not have to round off the findings because this is the true length of the bar.

When to replace the chain saw bar.

As much as chain saws are made from tough material, it is inevitable that they will get famished overtime. They perform tough tasks of cutting wood and trees and the bar will get affected. Certain indications will show you when it’s time to find a replacement bar.

  • If your chain saw bar is not straight, it is about time you got another one. You can observe the alignment of the bar by removing it from the body of the chain saw and laying it flat.
  • If your bars are twisted, this represents a version of a bent bar. These saw bars are usually straight on one side and twisted on the other. To observe this, sight the bar on flat ground.
  • If the parts of the chain saw bar that holds the chain- rails are broken or pinched. Rails that are damaged will not hold the chain for long and can cause a kickback injury; nobody would want that so it would be best if you got another bar.
  • A chain saw that functions properly should give smooth and strain-free cuts. If you are not getting anything close to this, you need to counter check the condition of the bar; it might be damaged. Crooked cuttings are an indication of a damaged bar.

How to measure a chain saw chain

I believe that you have gotten a clear understanding of how a chain saw bar is measured, its time you learn how that of a chain is measured. The chain does the actual cutting and is fitter on the chain saw bar rails. You must find a chain that fits into your chain saw bar to drive the saw with the right tension. When you measure a chain you need to know 2 things; pitch and gauge.


It is determined by measuring the length between any centers of three rivets then dividing the result by two. It improves your accuracy and precision while cutting.

  • Find the distance between 3 rivets- connectors found on the chain, one after the other. Pick theconsecutive rivets randomly.
  • Measure the length from the first rivet to the third one.
  • Divide the acquired measurement by two.
  • This is the pitch of the chain.


It measures how thick the drive links are. You need a tool to measure the gauge; you will have a hardtime without one. To avoid getting stuck, most people share a trick known as the coin method.

  • Get a quarter, penny and dime.
  • Fit each coin between grooves on the chain saw bar. The coin that fits into the grove without being forced is the right gauge. Amazing right!
  • A quarter represents .063 inches. A dime represents .050 inches. A penny represents 0.58 inches.
  • If none of the coins fits into any groove, the gauge is most likely .043 inches.

Chain saw chain size chart.

We are giving a list of the most common gauges and pitch for chain saws. Every brand uses their unique numbering system for these measurements. However, these details can be found online.

¼ inch .043 inch
.325 inch .050 inch
3/8 inch .058 inch
3/8 inch low-profile .063 inch

So far, the most usual pitch you might come across are the 3/8 inch and 3/8 inch low profile.

Chain saw chain size chart

With all of theses said, you do not have to find the measurements of the chain if this is too complicated for you. Good thing that most chain saws have printed the pitch and gauge on the side of the saw. You can also look up in the manual.

Frequently asked questions.

Q: Can I replace the chain without getting measurements?

A: When it comes to measuring the chain saw chains, this is not the safest method. This is because of the danger involved; the chain saw chain is the part that does the actual cutting. And yes you can replace a chain saw chain without measuring. Here are other alternatives:

  • You can easily find the pitch and gauge information written on the side of the chain saw itself, how convenient! Meaning that all you will require to do is finding the chain saw bar length, which won’t be much of a problem. As mentioned earlier, having a user manual can save you from all the processes involved unless you want to try it out yourself.
  • When purchasing a chain saw chain for the first time, remember to record the gauge and pitch and effective length you are using. This will help you for future reference; when it comes a time- which I know will, that you need to get replacement parts you need only to refer to the record.
  • It’s amazing how an experienced chain saw operator can make accurate guesses on the chain saw measurements by just looking at it. Although it is not safe to use this method as it could cost you back and forth trips to the store. It is better to be sure.

Q: When do I replace my chainsaw chain?

A: There are red flags that act as indicators of reduces chain saw efficiency and a spoilt chain is one of the causes. Try looking out for the instances below.

  • If the saw blade is dull.
  • If there are missing links on your chain.
  • When the chain starts to rattle around during cutting.
  • When the blade starts cutting in one direction and not the other.
  • When you have difficulty in pushing the chain guide and start forcing the chain into the wood.

Q: What is the cause of kick back on my chain saw?

A: A kick back may take place when the tip of the guide touches something or when the wood moves in and clutches the saw chain in the cut. Contact with the tip may at times cause a reverse action, kicking the guide bar back facing the user. Clutching the saw chain may quickly push the guide bar towards the operator. These events will make you lose grip of the saw and result in an injury. However, various inbuilt features can reduce the chances of occurrence of a kick back. There are low kick back chains and reduced kick back bars which are available for most power heads. You can also use a quick stop chain brake that reduces kick backs.

Q: What is the best chain saw bar length?

A: The length of the bar is dependent on the size of your chain saw. If your chain saw is large and more powerful, it means that you use it for heavy logging or woodcutting. Larger chain saws have bar lengths of above 20 inches. If you are a home or ranch owner, the tasks involved are not intensive; mostly firewood cutting. Therefore your chain saw will be medium or small-sized whose bar length is between 12 and 20 inches. When cutting, ensure that the bar length of your chain saw is 2 inches longer than that of the tree or wood.

Final Words

I hope that you know how to measure a chain saw bar and chain. Now that you have gotten the correct measurements of your chain and bar, you can confidently go to the store and ask for the replacement parts. Bring the readings with you for confirmation. After purchasing the replacement parts, you can replace the old ones.

Follow the same process of undressing the chain saw by removing the bolts and cover. Remove the old bar and replace it with the new one placing it on the interior bolts. Set the chain on the bar and adjust it to the right tension and fasten the bolts after putting back the cover. Be assured that your chain saw will be back in action like there was nothing wrong.

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