How Many Watts Does A Circular Saw Use?

August 24, 2022

Using wired circular saw on woodworking projects.

An intelligent buyer of any power tool such as the circular saw would surely ask about the wattage of the prospective circular saw he intends to buy. The reason is that the knowledge of the circular saw’s wattage matters. But more often, when you buy a circular saw, you will only see the running wattage, but seldom will you find its starting wattage in the product description. But the starting wattage is also important to know before you purchase the circular saw.

Electrical power, of course, gets measured in watts. A watt, for example, is a single unit of electrical power. It refers to the transfer rate of electrical power. Moreover, it is the amount of energy consumed by an electrical tool. So, when you look at the wattage used by a circular saw, you are looking at the circular saw’s power requirements.

Starting Wattage and Running Wattage

Many power tool users assume that power tools like circular saws come with only running wattage. Yet, they are mistaken because a circular saw, for example, comes with a starting wattage and running wattage. These two wattage measurements become more critical if you’re using a generator. 

A standard circular saw, for example, necessitates 2,400 watts as its starting wattage, while it needs only 1,200 watts for its running wattage. The starting wattage occurs when you switch on the circular saw, and electrical power surges into the wires of your circular saw and makes the saw blade spins. 

Once it has started, you will only need 1,200 watts to keep its blade spinning. A larger circular saw, of course, will require higher watts to keep it running, while a smaller circular saw will need fewer watts.

Other Factors That Can Help You Know the Power Needs of Your Circular Saw

You can use the circular saw for ripping and crosscutting lumber. Hence, you need to know its cutting power. But to evaluate its cutting power, you need to take note of the watts it consumes. It might be a very powerful circular saw if it uses more watts. Below are the other factors you need to be cognizant of to understand the power requirement of your circular saw:


You will often see the amperage in the fact sheets of the circular saw. It indicates the amount of electricity drawn by the motor. The majority of circular saws consume 15 amps. Some circular saw models, however, like the Skil’s 5755 use fewer watts.

Rotations Per Minute (RPM)

The circular saw motor uses power to create the needed torque to rotate the circular saw blade. The power rating of the circular saw gets usually measured in rotations per minute or RPM. You will find that the majority of the circular saws feature 4,000 rpm. You will also find high-end circular saws with 5,000 rpm or greater. The higher the rotations per minute of the circular saw, the more powerful it cuts.

Amperage measures the electricity drawn by the motor. The RPM, however, provides you with a clearer understanding of how the drawn power affects the circular saw’s performance. 

It will be good to note that circular saws can be sidewinder or worm-drive saws. These two types of circular saws feature different orientations. The worm-drive circular saw, for example, will generate more torque compared to the sidewinder, despite having the same power requirement. 

On average, the 7-1/4″ circular saw is capable of 5,800 rpm. This speed gets usually translated into 125 mph. Some high-end circular saw models, like Bosch’s CS20, can deliver up to 9,600 rpm.

Frequently Asked Questions

Aside from knowing the difference between the starting wattage and the running wattage and familiarizing yourself with the other factors to consider to understand the power rating of the circular saw, it will also help to familiarize yourself with the following FAQs about the power consumption of your circular saw, for they might also be the questions you have in mind:

Will the Circular Saw Require an Uninterrupted Power Supply?

The answer to this question is yes. If you’re using a corded circular saw, it will need an uninterrupted power supply to run. However, you can also use a cordless circular saw run by a battery. Of course, the cordless circular saw doesn’t have an uninterrupted power supply because the battery can run low bat anytime. 

How to Minimize the Power Consumption of Your Circular Saw?

If the starting wattage is higher, you can lessen the power consumption of your circular saw by minimizing the on and off switching of your circular saw. Ensure that you will switch it on only when necessary. In this way, you can reduce the power consumption of your circular saw. 

Does the Circular Saw Exhibit Power Loss?

Well, a circular saw also exhibits power loss. Yet, these power losses are only minimal. Additionally, you can reduce the consumption of power of your circular saw by regularly cleaning the saw blade. Ensure likewise that the moving parts of your circular saw get lubricated to reduce power loss due to friction.


As mentioned above, it is important to know the power rating of a circular saw before buying it. The power rating, of course, is usually indicated in amperage, wattage, and rpm. The standard today is the 15-amp circular saw. Besides, the average running wattage of most circular saws is 1,200 watts, while the majority of circular saws run at around 4,000 rpm.

It will be good to note that even if two circular saws have the same amperage rating, they are not the same. For example, a worm drive can transfer more power to its saw blade than the sidewinder. Thus, the circular saw with a worm-drive design will offer more torque than the sidewinder circular saw.

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