16 vs 18 Inch Chainsaw: Which Bar Length Do You Need?

Choose a chainsaw bar about 2 in longer than the wood you usually cut. A 16 in bar suits branches, storm cleanup and logs up to about 14 in thick, and is lighter and easier to control. An 18 in bar suits regular firewood cutting and logs up to about 16 in, but needs a stronger engine and more care.

If you’re not sure, the shorter bar is the safer choice: most homeowners rarely cut logs bigger than a 16 in bar can handle.

16 vs 18 inch chainsaw at a glance

	16 in bar	18 in bar
Ideal wood diameter	Up to about 14 in	Up to about 16 in
Typical gas engine	About 35 to 45 cc	About 40 to 50 cc and up
Battery saws	Common	Fewer models; high-capacity batteries
Weight and balance	Lighter, easier to handle	Heavier, more nose-heavy
Best for	Pruning, limbing, storm cleanup, small firewood	Regular firewood, felling small to medium trees
Control for beginners	Easier	Harder

Engine sizes are typical; each saw’s manual lists the bar lengths it’s designed for.

How bar length affects cutting

• Cutting capacity: a bar cuts wood up to about its own length in one pass. With good technique you can cut wood almost twice the bar length from two sides, but that’s slower and more dangerous.
• Power: a longer bar carries more chain, which needs more power to keep the speed up. A long bar on a small engine cuts slowly and stalls.
• Control: a longer bar is heavier at the front and harder to hold steady, especially when limbing and pruning.
• Kickback: kickback happens when the upper tip of the bar touches wood. A longer bar puts that tip farther from your eyes, so it’s easier to touch something by accident.

Which length for your job?

Job	Bar length
Pruning and limbing	12 to 14 in
Storm cleanup and small trees	14 to 16 in
Home firewood	16 to 18 in
Large logs and felling bigger trees	18 to 20 in and up

Changing the bar on your saw

A saw can only take the bar lengths its maker lists for that model, and the chain must match the bar’s length, pitch and gauge. To find what your saw has now, see how to measure a chainsaw bar and chain.

Looking after the bar

A longer bar puts more load on the oiler and the engine:

• Keep the oil tank full and use the right bar oil; can you use used motor oil for chainsaw bar oil explains why used oil is a bad idea.
• Keep the chain sharp and correctly tensioned.
• A saw that runs poorly with a longer bar may need its carburetor adjusted or replaced; see best aftermarket chainsaw carburetors.

Related guides

• How to Sharpen a Chainsaw: File vs Electric Sharpener