What Is a Chain Saw? | Types, Uses & Buying Basics

Whether you’re clearing storm damage, bucking firewood, or pruning overhead branches, the chain saw is one of the most versatile tools a property owner can own. Understanding what a chain saw is — and how the different types differ — matters more than you might think. The right saw for one job is the wrong saw for another, and choosing by task rather than by impulse saves both money and effort.

How a Chain Saw Works

A chain saw cuts with a motor or engine that drives a continuous loop of chain around a steel guide bar. The chain carries sharpened cutting teeth that bite into wood as the bar is pushed through the cut. Three primary components make up every saw: the power head (engine or motor), the guide bar, and the chain itself.

The cutting action is straightforward, but the chain’s fit is not. Chain pitch and gauge must match the drive sprocket and bar tip exactly. Common pitches include 1/4 in.,.325 in., 3/8 in., and.404 in. Common gauges run.043 in.,.050 in., and.058 in. Mixing these creates poor performance and a potentially dangerous fit.

What Are the Main Types of Chain Saws?

Chain saws are classified primarily by power source, and that choice determines where and how you can use them. Gas, electric, and battery/cordless models cover nearly all homeowner and professional work. Hydraulic and pneumatic versions exist for specialized industrial and rescue use.

• Gas-powered saws offer the most power and run time. Displacement under 3.8 cubic inches (62.3 cc) puts a saw in the consumer class; larger engines are professional-grade.
• Electric corded saws are lightweight, quiet, and great for smaller jobs near an outlet.
• Battery/cordless saws give cord-free convenience with less noise. They suit light to mid-range work.

Gas saws are strictly outdoor tools due to exhaust fumes.

Choosing the Right Bar Length and Engine Size

Bar length and engine size should match the wood you actually cut, not the biggest log you can imagine. Bar lengths in consumer saws commonly run from 12 in. to 36 in. or more. A 14–16 in. bar handles most light homeowner work, while 18–20 in. suits larger diameter cutting.

A saw class chart helps you match tool to task:

Long bars increase reach, but they also put more of the hazardous tip farther forward. Size the bar to the task, not to the biggest possible log. A longer bar on a small engine also cuts slower because the motor must pull more chain.

If you’re shopping for a compact model for yard work, our roundup of the best small chain saws for homeowners covers tested options that balance power and handling.

What Is a Chain Saw Used For?

Chain saws handle a wide range of outdoor work. The most common U.S. uses include felling trees, limbing, bucking logs into firewood, pruning, land clearing, and storm cleanup. Some users also run carving saws for sculpture work, and rescue crews use specialized models for extraction.

Saw selection follows the task at hand. Forestry guidance from the USDA’s equipment catalog shows this clearly: a 40cc motor with a short cutter bar suits pruning, a 50–70cc motor with a 30–45 cm bar handles thinning, and clear-fell work calls for an 85cc motor with a 60 cm bar or larger.

One important distinction: a pole chainsaw (or pole saw) is a separate pruning tool — a small chain saw head mounted on a long pole. It’s designed for reaching overhead branches without a ladder, not for general cutting.

Before buying any chain, verify its pitch and gauge against your specific bar and sprocket. Chains are matched to saw classes, with different pitches made for small pruners, small-to-medium saws, medium-to-large saws, and large specialty cutting. Stihl’s chainsaw buying guide walks through matching bar length and chain specs to your intended work.

Both “chainsaw” and “chain saw” are standard, correct terms — dictionaries and manufacturers use them interchangeably. Whichever you call it, matching the saw to the task keeps cutting safe, efficient, and within the tool’s design limits.