If you are looking to buy a new leaf blower, you may ask yourself: “what is CFM in leaf blowers.” This specification seems to come up constantly. And it can be confusing to know if MPH is better than CFM. In some cases, you may think that faster is better—in other words, MPH is more important. But very often, the volume of air passing through the blower’s tube (CFM) is a better indicator of how suitable the leaf blower is.
When you buy a corded, cordless, or gas leaf blower, you want it to do one thing—blow debris fast and efficiently. However, a leaf blower has multiple uses when clearing a yard. The most obvious use is for blowing piles of leaves in the fall. But there is a difference in shifting light, dry leaves, or moving heaps of soaking wet leaves. A leaf blower is also helpful for clearing light snow, grass clippings, small stones, gravel, or branches.
Before buying any leaf blower, you must consider CFM and MPH. But, if you have a corded or battery leaf blower, amps and voltage are essential factors. But if you are comparing gas leaf blowers, then horsepower, engine displacement (cc), and fuel capacity are necessary specifications to take into consideration.
This article aims to blow away the confusion about CFM and how necessary airflow is when buying a leaf blower. From all the specs to consider, CFM is probably the most critical. You will also learn why MPH is also a vital specification when looking for a high-quality leaf blower.
What is Leaf Blower CFM?
Leaf blower CFM is short for cubic feet per minute. This measurement is the volume of air passing through the blower’s nozzle. The motor in the leaf blower creates a vacuum effect, drawing in air, creating strong airflow. So it’s the cubic feet of air moving in a minute.
How to Calculate CFM
To calculate CFM (cubic feet per minute) or airflow rate, it’s essential to know the diameter of the tube and the speed of air (MPH). This is because the width of the leaf blower’s hose directly affects the level of airflow. Additionally, how fast the blower moves air depends on the nozzle’s size.
Rather than learning complicated equations to calculate CFM, it is best to see how CFM and MPH compare when deciding on the best leaf blower to buy.
CFM vs. MPH — What’s the Difference?
Cubic feet per minute (CFM) measures the amount of airflow a leaf blower produces. Miles per hour (MPH) is the speed at which the air leaves the nozzle.
Here are a few simple examples to understand how to measure a leaf blower’s cubic feet per minute.
Suppose you have a leaf blower with a tiny nozzle, but it has an impressive air speed of 200 MPH. While the rate seems remarkable, it won’t shift many leaves because of the thin jet it creates. The narrow nozzle doesn’t produce good airflow and displacement to blow away leaves. This type of blower has high MPH but very poor CFM.
Next, imagine a leaf blower with a massive nozzle, say the size of a large sewer pipe. This large nozzle can displace more air than the tiny one in the first example. But if the blower only has a speed of 50 MPH, it won’t be enough to blow anything. At best, it will only cause a slight draft.
For the last example, let’s say that the leaf blower has a 4-inch nozzle and a speed of 160 MPH. This type of blower would be the best one from our examples. The powered leaf blower has good speed, and because the nozzle is the optimal width, the airflow is enough to move wet leaves, gravel, and other debris from your garden
You can imagine what happens when water goes through the garden hose. The more you squeeze the end, the faster the water comes out. If you don’t squeeze tight enough and there is weak pressure, the water stream won’t travel far. However, compress it too much, and the stream of water becomes thinner, meaning you need to work harder to water the garden.
So you need the optimal balance of speed and width of hose. In other words—a good balance between leaf blower CFM and MPH.
How Many CFM Do I Need in a Leaf Blower?
The cubic feet per minute you require from a leaf blower depends on the size of the job and property size. For smaller properties and occasional leaf blowing, small handheld blowers with 300 to 400 CFM are suitable. If you only clear driveways and hard surfaces, then a cheap battery-powered leaf blower with 100 CFM should be fine. But if you need to clear piles of wet leaves from large grass areas, then a powerful corded blower or a gas leaf blower with 400 to 700 CFM is best.
What is a Good CFM for Corded Leaf Blowers?
Typically, corded leaf blowers have a CFM rating between 200 and 600. Corded leaf blowers tend to be lighter and easier to handle than battery cordless leaf blowers or gas leaf blowers. Most corded leaf blowers are handheld, lightweight models.
What is a Good CFM for Cordless Leaf Blowers?
Cordless leaf blowers use rechargeable batteries, and they can be as powerful as corded leaf blowers. You can expect up to 600 CFM from a good quality cordless leaf blower. However, it’s good to remember that they are more expensive and heavier than corded models.
What is a Good CFM for Gas-Powered Leaf Blowers?
A gas leaf blower can be a handheld or backpack model. Gas-powered leaf blowers have a more powerful engine and can create an airflow up to 1,000 CFM. Some commercial gas leaf blowers can reach a whopping 2,000 to 3,000 CFM.
Do different types of leaf blowers have different CFM?
Most residential leaf blowers—corded blowers, cordless blowers, handheld blowers, and gas blowers—have CFM and MPH values in a similar range. Typically, low-end, cheaper leaf blowers have a poor 100 to 200 CFM. But mid-range and top-of-the-range models usually have between 300 and 700 CFM.
Are CFM values a reliable guide?
CFM values are a reliable guide to know how fast you can clear your yard of leaves. For example, some of the best corded and cordless leaf blowers deliver up to 600 CFM with an airspeed of only 110 MPH. However, cheaper leaf blowers may deliver as little as 180 CFM with an airspeed of 180 MPH.
In Conclusion
CFM is a vital specification that lets you know how many cubic feet of leaves a leaf blower can move in a minute. A leaf blower with a fast speed doesn’t always mean less work. Look for a good balance of airflow (CFM) and speed (MPH). The bottom line? Always look for CFM, not MPH, when choosing a suitable leaf blower.