How to Measure a Chainsaw Bar
To find how long your chainsaw bar is, measure from the front of the saw body to the bar tip, not the full bar from end to end. Confirm the size in your manual or on the bar, then match the replacement bar and chain to your saw.
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To find how long your chainsaw bar is, measure from the front of the saw body to the bar tip. That exposed cutting length is the nominal bar size; the full metal bar is longer because part of it sits inside the saw.
Knowing the stated length helps you identify your current setup and shop for compatible replacement parts. For a wider overview of saw types and sizes, see our chainsaw guide.
How do you measure a chainsaw bar?
Measure the exposed bar from the point where it exits the saw body to its tip. Keep the tape straight along the bar and measure in inches.
Don't measure the entire metal bar from the powerhead to the tip. The hidden section under the saw body is excluded from the nominal length.
If your measurement is between whole-inch sizes, round up to the nearest whole inch. For example, an exposed length a little over 17 inches is generally treated as an 18-inch bar, but check the manual or bar marking to confirm.
Where can you confirm how long your chainsaw bar is?
Check the owner's manual and the markings on the guide bar. The manual identifies approved equipment for your saw model, while a stamp or label on the bar can show its nominal length.
Bar markings may be near the mounting end or along the bar body. Clean off sawdust and oil gently so you can read the stamp, and don't remove material or scrape aggressively to find it.
If the markings are missing, use the exposed-length measurement as a clue, then verify the model's approved bar size in its manual. A measurement alone does not confirm that a replacement will fit.
What measurements matter when replacing a bar?
Bar length is only one part of fit. The replacement bar and chain must match the saw's mounting pattern and the chain's pitch, gauge, and drive-link count.
Pitch describes the chain size, while gauge is the thickness of the drive links where they sit in the bar groove. Drive-link count is the number of links that run around the bar and sprocket.
Check the saw model and manual before ordering. Our guide to best replacement chainsaw guide bars can help you compare bar options after you know the required specifications.
Why check the chain as well as the bar?
A bar and chain need matching specifications to work together. A chain with the wrong gauge may not fit the groove, and pitch or drive-link differences can prevent correct installation.
Oregon recommends checking the number stamped on the old chain's drive link or consulting the saw manual to confirm pitch and gauge. For help identifying dimensions, see our best chainsaw bar and chain measuring tool guide.
What if you need a replacement bar and chain?
Choose a replacement only after confirming the bar length and all fit details for your saw. These examples show why size labels alone are not enough to establish compatibility.
The Oregon 20-inch combo is specified for a 20-inch bar, .325-inch pitch, .063-inch gauge, 81 drive links, and a D025 motor mount. Its stated compatible models include several Stihl saws, with gauge qualifications for some models.
A longer replacement is not automatically suitable just because it matches your current bar's nominal length. Confirm the model, mount, chain, and manual requirements before choosing among chainsaw guide bars.
The Poulan Pro guide bar is 18 inches, with 3/8-inch pitch and .050 gauge. It is designed for select Poulan Pro chainsaws and chains, so verify the saw model before considering it.
The Oregon 18-inch combo is specified for an 18-inch bar, .325-inch pitch, .050-inch gauge, 72 drive links, and a K095 mount. Its stated fit includes a range of Husqvarna models up to 55 cc.
These products are examples of different size and fit combinations, not interchangeable options. Match every listed requirement to your saw before buying.
Can you use a chainsaw with a longer bar?
**Use only a bar length approved for your chainsaw model. For compact branch work, compare mini pruning chainsaws and confirm each saw’s approved bar size.
For safe operation, read how to use a pruning chainsaw.** A longer bar can change the saw's handling and must be supported by the saw and matched to the correct chain.
Don't assume that a bar will fit because its length seems close. Check the manual for approved bar lengths and verify the mount, pitch, gauge, and drive-link count for the complete setup.
If your main job is cutting firewood, our guide on what is a good chainsaw bar length for firewood? explains how to think about bar size for that task. For overhead trimming, compare a pole saw and pole pruner instead of choosing a longer handheld chainsaw bar.
When should you replace a chainsaw bar?
Replace a bar when wear or damage makes it unsuitable for safe, even chain travel. Inspect the rails and groove as part of routine maintenance, and follow the saw maker's service guidance.
For EGO saw lubrication, read how to oil an EGO chainsaw.
A bar that is worn unevenly, bent, cracked, or damaged around the groove may need attention. Some wear can be addressed with the right maintenance tools, but damage that affects the bar's condition calls for replacement.
Read our guide to when to replace a chainsaw bar for signs to look for. If repair is appropriate, see best chainsaw bar repair tools before deciding what equipment you need.
How long is your chainsaw bar?
For anyone asking how long is my chainsaw bar, measure the exposed cutting length from the saw body to the tip, then confirm the nominal size on the bar or in the manual. Measure carefully because the full metal bar includes a hidden section that doesn't count toward the stated length.
Before replacing a bar or chain, match the saw model, mount, pitch, gauge, and drive-link count. The correct choice is the one approved for your saw and job, not simply a longer bar.
Frequently asked questions
How do I measure a chainsaw bar?
Measure the usable cutting length from where the bar exits the saw body to the bar tip. If the measurement falls between standard whole-inch sizes, round up to the nearest whole inch.
Check the manual or bar markings to confirm the stated length.
Is chainsaw bar length the full length of the metal bar?
No. The stated chainsaw bar length is the exposed cutting length from the saw body to the tip, not the full metal bar from end to end.
The section covered by the saw body is not included in the nominal size.
How can I tell what size chainsaw bar I have?
Look for a length marking stamped or printed on the guide bar, then check your chainsaw manual to confirm it. If the marking is worn or unclear, measure the exposed cutting length from the saw body to the bar tip and compare it with the manual.
Can I put a longer bar on my chainsaw?
Only use a bar length approved for your saw model. A longer bar also needs a compatible chain with the correct pitch, gauge, drive-link count, and motor mount, so check the manual and bar specifications before changing sizes.
