What Size Chainsaw Do You Need? (Complete Buyer Guide)

Last Updated on May 2, 2023 by Barry Gray

If you are cutting down trees, or if you are lopping branches, or if you are processing logs into sections, you will need a chainsaw. But even once you’ve decided on electric or gas, there’s an overwhelming array of options for size. So, what size chainsaw do you need?

Selecting the right size chainsaw has a lot to do with being wise about one’s experience level and requirements. Cutting larger diameter trees and logs will require a longer bar; however, shorter bars are generally safer. Fitting a saw with a shorter bar will help you get more power.

You want to get a chainsaw sized appropriately for the work you will be using it for and one that you can use safely. Several factors come into play. I’ll examine these factors so you can choose wisely. 

chainsaw size

A Brief Look At Chainsaw Types And The Sizes They Come In

Electric Powered Chainsaw Sizes

Electric chainsaws run from a rechargeable battery and come in corded or cordless options. They are generally less powerful than gas-powered chainsaws, although the upper-end models overlap in power with the smaller gas-powered engines.

Electric chainsaws require very little maintenance, are easy to use, more lightweight, and generally quieter. They are ideal for light to moderate work, with an occasional more significant job.

Electric Powered Chainsaw

They are usually offered in 8 to 18-inch bar lengths, although longer bars exist.

Their engine sizes generally run between 20 and 60 volts in cordless models and 9 and 15 amps in corded models. Although higher strengths can handle longer bar lengths better, you may want to keep to lower bar lengths for work around your property.

I would recommend these perfect for light firewood cutting, small tree cutting and bucking, trimming and pruning, and construction work.

Gas Powered Chainsaw Sizes

Gas Powered Chainsaw

Gas-powered chainsaws run off a 2-cycle engine and need a mixture of fuel and gas to run correctly. As a result, they need more maintenance than electric models. 

These powerful machines vary more in size than electric-powered models, and there are some massive examples in the professional logging industry, with bar lengths of 5 feet or more.

Most gas-powered chainsaws for residential use are between 16 and 24 inches in bar length and powered by 32 to 62cc engine displacements. 

I would use one of these powerful machines for logging, lumber milling, firewood cutting, or cleanup.

How To Select The Right Size Chainsaw

To select the correct size chainsaw to purchase for your immediate needs, I advise you to consider the following two questions in detail and answer as honestly as possible.

This is no time to be macho about what you require and buy something oversized for your needs. On the other hand, don’t land up with something too small to do the jobs you require it for.

What Size Jobs Are You Going To Tackle With Your Chainsaw?

Consider what size jobs you are going to tackle with your chainsaw. The size of jobs will determine what size chainsaw and bar length you require. You will then be better positioned to select what you need to have versus what you want to have.

What Experience Do You Have Using A Chainsaw?

If you have little or no experience using a chainsaw, I would advise you not to tackle any large jobs with one, as you will endanger yourself and possibly others. Hire a professional.

To get experience using a chainsaw under safe conditions, I recommend taking classes on chainsaw use and safety through a local extension office.

What Size Of Chainsaw Engine (Or Battery) Do You Need?

If you are going to be doing lighter work such as pruning and light firewood cutting, I recommend that you get a smaller chainsaw in the range of 20 to 40 volts for electric or 32 to 40cc for gas.

If you are regularly doing heavier work such as felling small trees, and you have the necessary experience to use a larger chainsaw safely, consider getting something in the range of 40 to 60 volts for electric or 40 to 62cc for gas.

What Guide Bar Length Do You Need In A Chainsaw?

guide bar Chainsaw

The length of the guide bar is an essential consideration once you have answered the preceding questions. 

A longer bar, and hence a longer chain, requires a more powerful engine to drive it. As a result, longer bar length usually correlates with heavier engines and increased vibration.

These factors result in user fatigue throughout long jobs. As you get tired, the chances of having an accident rise. Using a chainsaw that is not more powerful than required for the job is an excellent way to stay safe.

I recommend using a short bar. Shorter bars are generally safer, and they allow the use of chainsaws with smaller engines, which reduces strain on your muscles and back.

The general guideline that most operators agree on is that a chainsaw should have a bar length 2 to 3 inches longer than the diameter of the tree or limb you wish to cut.

To cut a 10-inch tree in one pass, you will need to use a 12-inch bar. However, because you can cut a larger tree in more than one pass, there is a way to cut a tree whose diameter is more than twice the length of your bar: by making a bore cut into the middle of the notch.

However, you may be regularly cutting larger trees, say 16-inch diameter. You will want to reduce your working time and lessen your chances of fatigue by getting a chainsaw with a larger bar size to make your cuts in a single pass.

Can You Change The Bar Size On A Chainsaw?

In Europe, saws up to 60cc commonly only have bars between 13 and 15 inches, whereas, in the US, manufacturers fit even 35cc saws with 16 or 18-inch bars. The typical result is that performance suffers. 

I suggest you consider putting a shorter bar onto your chainsaw, as the ideal ratio between engine displacement in cc and bar displacement in inches is  3:1 to 4:1. Doing so will result in you getting more power out of your chainsaw.

Be aware that different saws have different bar designs, and the bar also has to match the chain/sprocket configuration. It is best to chat with a dealer to ensure that everything works together nicely.


When selecting the correct size chainsaw, you should weigh up your experience and needs. Don’t be tempted to get something larger than you need, as shorter bars are generally safer. Fitting more powerful chainsaws with a shorter bar is a way to get more usable power.

Contact your local extension office and get some classes if you don’t have much experience using a chainsaw.

Photo of author

Barry Gray

Hi, I’m Barry. I’ve loved woodworking and bringing things back to life for more years than I care to remember. I hope my passion for tools comes across loud and clear in everything you read here on The Tool Square.

Leave a Comment