Chainsaw‌ ‌Files‌ ‌Size‌ ‌Chart‌

If you buy something through our posts, we may get a small commission. Read more here.

In my line of work, I’ve learned a lot from some seasoned loggers and engineers, and one thing they’ll emphasize is the importance of a sharp chain. A high-performance chainsaw does all the work for you, but the same cannot be said for unsharpened chains. 

Also, using the wrong file size may result in excess sawdust and unforeseeable accidents. Fortunately, this article will discuss everything you need to know about picking the right file size. Doing so enhances both the chain’s sharpness and your user experience.

What Is a File Size Chart?

Chain Type Chain Pitch Size (mm) Size (inches) 
25, 91 ¼” 4.0 5/32
90  0.325” 4.5 11/64
20, 21, 22, 95 ⅜” 4.8 3/16
16, 18, 26, 27, 72, 73, 75 0.404” 5.5 7/32

As you can see, the file chart displays the different saw chain types and sizes. For accurate results and maximized sharpness, the file size must match the depth gauge code number or the chain pitch, which is estimated between three rivets.

How Can You Determine the File Size of Your Chainsaw Chain?

When looking for topnotch chainsaw files, the chainsaw file size chart is your best friend. Always refer to the values on the table so that you know which files to buy. For example, if you have a chain with an ID number of 95, a 4.8 mm round file would be the most compatible option. 

Husqvarna 460 Rancher Chainsaw

When it comes to identifying the right file size, it can be a bit tricky sometimes. If you’re having trouble finding the ID number, take a look at the chain pitch – it often hints at the required tool size. 

And if you’re still unsure, reaching out to your local store or researching the manufacturer’s recommended file sizes is a reliable approach. Keep in mind that some specifications might differ from the chart I provided earlier.

What Is a Chainsaw Chain?

Now that we have gone over the file size chart, let’s discuss the chainsaw chain with its direction in terms of its construction and overall appearance. [1]

The chain contains two cutters, one on the left and the other on the right. They surround the entire chain in an alternate pattern to maintain uniformity in the cutting. Another important part of the chainsaw is the depth gauge, which determines how deep the chain can penetrate the wood.

(Looking for a budget-friendly chainsaw? Here are the best chainsaws below 200 we reviewed. Read next!)

What Are the Different Types of Chainsaw Gauges and Files?

Chainsaw File Size

As we will see on the graph, the primary file options are 4.0 mm, 4.8 mm, and 5.5 mm. It comes in either a round file or flat file depending on the type of cutter you are planning to sharpen. More on the cutters later on.

Flat File and Gauge

The gauge is a key tool when it comes to configuring your files. It plays a pivotal role in establishing the correct depth gauge, which is a vital element of the chainsaw, as it dictates the cutting depth of the chain.

Greenworks 40V 16-inch Cordless Chainsaw

Here are the available sizes: 

The general rule of thumb is to go for gauges that measure at least 0.050 or above for a longer life span.

Gauge Measurement

The gauge measurements and readings are found on the chainsaw’s bar guide. These labels are a big help because they provide accurate and precise gauge measurements. Thanks to the markings, you won’t have to guess or estimate the gauge’s size when applying the files.

(For an excellent cutting work, you can complement your chainsaw blade with top-performing chainsaw mills I reviewed here. These will make you work faster and so much easier, too!)

What Are the Different Types of Cutter Teeth?

When choosing a chainsaw file, you need to understand the different types of cutter teeth your chain uses. That is because you want your chosen files to be compatible with the cutter teeth, meaning they are neither too big nor too small. Let’s go over them one by one.

Oregon CS1500 Lightweight Chain Saw

Chipper or Round Tooth

First up is the round tooth, the easiest one to file among the three cutters. One advantage it has over its chisel counterpart is its ability to resist dust and dirt. 

That’s why it’s commonly used even in high-power chainsaws. Moreover, its curved shape makes it a viable option for those who need a chin that can cut thoroughly.

Semi-Chisel (Round Grind and Square Tooth)

Of the three types, the semi-chisel has the best dirt and dust resistance. It is also capable of staying sharp for extended periods. When working with this type of cutter, I’ve found that a round-shaped file, used alongside a guide, works best for the job.

Chisel (Square Grind and Square Tooth)

The full chisel cutter is the sharpest, so you need to make sure you seek help from professional sawyers to avoid injuries. You will need a square file that fits the cutting edges and the chain’s square shape for filing purposes, especially when it shows an uneven cutting teeth.


The correct chainsaw file size can make a world of difference. It not only reduces the amount of sawdust produced, lowering the risk of your air filter getting clogged, but pairing a top-notch professional chainsaw with a well-maintained chain can also ease the strain on your arms, boosting efficiency.

Always ensure you pick the right chain type and size. And if ever in doubt, don’t hesitate to consult our size chart.

robert headshot

Robert Johnson is a passionate furniture maker & carpenter, sought after for his knowledge on the craft.
You’ve probably seen his down-to-earth wisdom in USA Today, Bobvila, Family Handyman, and The Spruce, where he has shared commentary and guidance on various woodworking topics.

Robert is the brain behind Sawinery, where he aims to share tips, tricks, and a passion for all things carpentry.

Related Articles
Join our community on facebook and get 3 woodworking plans for free!