How Many Watts Does a Circular Saw Use?

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According to popular belief, circular saws are more powerful when they are faster. However, this is not the total case. A circular saw’s power is determined by its wattage rating. 

In technical terms, power is time-based work measured in watts. The higher the wattage rating, the more effective the saw. So, how many watts does a circular saw use? Read on to find out.

How Much Power Does a Circular Saw Consume in Watts?

As their name implies, circular saws do not have a blade that cuts along a single axis. Rather, they use the power provided to drive their blade in a circular movement. 

Therefore, the power provided to the saw is transformed into a circular force, also known as torque. So how much power does the saw need to work effectively?

Rotations Per Minute (RPM)

As explained, it is not the speed or RPM of a saw that determines how powerful it is. Several other important factors, such as the amps and wattage rating, determine how much power a circular saw uses. 

Skilsaw SPT77WML Worm Drive Circular Saw

The rotation per minute is also important because it allows the saw blade to spin faster and cut through the material at a fast rate. But the most important is the amps rating because this determines how much electricity is used and ‌how fast the blade can go.

Starting vs. Running Watts Used by Circular Saws

Another thing you have to pay attention to in choosing the right circular saw is the starting and running watts. 

The starting wattage is the time when tripping happens. The circular saw requires a high amount of power, and it goes off for some seconds and comes back on. 

Meanwhile, the running watts of this power tool are determined by its continuous or average power. The saw, once powered, creates an initial noise. And once it passes this stage, the saw should run smoothly until you turn it off. This process is what we identify as the running wattage of a circular saw.

Number of Watts Consumed by Circular Saws vs. Other Tools

This section will detail how many watts other tools consume versus a circular saw through a comparison table. This will make you understand the difference between these tools’ starting and running wattage to help determine your workshop’s basic power requirements.

cutting wood with circular saw

Furthermore, this information will give you insight into the power consumption of other tools you use for your woodwork and the type of power source (generator) you choose.


Starting Watts (W)

Running Watts (W)

Circular Saw









Electric Chainsaw



Electric Lawn Mower



Electric Pressure Washer



Electric String Trimmer



Jig Saw



Miter Saw



Orbital Sander



Paint Sprayer









Water Pump



Wet/Dry Vacuum






How Many Amps Does a Circular Saw Consume? [Watts vs. Amperage]

If you want to know how many watts and amps this saw can consume, most circular saws use 15 amps, the lower common capacity of home circuitry. 15 amps, in this case, reflect the amount of electricity the motor draws. 

In technical terms, this safely corresponds to about 1440 watts of power needed to run the motors continuously. Some models use less than 15A. An example is the Ryobi CSB141LZK, which uses 14A and Skills at 13 amps.

Skil 15 AMP 7-1/4 Circular Saw With Laser Guide

Recommended Generator Size for Circular Saw Usage

If you want to know how many watts you will need for a generator to run a circular saw, you will find it difficult to determine as there are no fixed values. 

The reason is that the rating of your generator depends on the tool you want to power. However, you can invest in generators with standard 7KW to 10KW. This can efficiently power all your tools.

Below is an estimation of how much power you can get for your tool using these generators:

  1. 7KW – This will give you about 3,300 to 4000 watts of useable power and 3100 to 3400 starting and running power
  2. 10KW – Expect about 6500 to 9500 watts of useable power and 6500 to 8500 starting and running power
SKIL SPT67M8-01 Sidewinder Circular Saw

Is a 2000-Watt Generator Enough to Run a Circular Saw?

We do not advise you to run your circular saw with a 200W generator. This is because the generator is too powerful and might burn out your motor within a few minutes. 

All that you need to run a circular saw is around ten amps. Although a 200W generator will give you that, the starting capacity, which is 15A, will be too much for the saw and will burn out the saw within 10 minutes. 

However, if you wish to get a portable 2000-watt generator for your saw, you can invest in a reliable and long one. 

What About a 1000-Watt Generator?

Yes, a 1000-watt generator can run a circular saw. However, you will need to make some adjustments. There is a difference between the running and starting watts. You must be aware of this when buying an inverter generator to power up your tools.

Let’s say, for example, your generator has starting watts of 5,500, it will run the circular saw with no hassle. 

However, if it has a starting watt of 3,300 watts and 4,025 to keep it running, it won’t be able to power up your saw. This is because of the difference between the starting and running watts.

Can a 900-Watt Generator Power a Skill Saw?

Yes, a 900-watt generator can power a skill saw. However, this is if it has a running wattage of at least 4,000 watts. 

Anything below this might not run the saw. You should opt for high-powered and reliable generators to be safer. Those ‌that will serve your purpose without giving you any headache. 

Can a Solar Panel Power a Circular Saw?

It is not possible to run a circular saw with a solar panel. It cannot supply the wattage required to drive the saw’s motor. If you have a 1000-watt panel, it can only supply you with 400-500WH of energy daily. 

This is far lesser than what your circular saw needs. Furthermore, most portable tools use 12v batteries, and it won’t sit well to use a solar panel to charge a 12V battery. This is not a wise decision.

solar panel

Can a Car Battery Power a Circular Saw?

No, this is not possible. The reason is that car batteries can only produce about 20A. This is the maximum it can generate, which is nowhere what you need to start your circular saw for 5 minutes.

However, if you wish to use a car battery to run your circular saw, the wattage must be around 100. This isn’t cost-effective, and it will be a good idea to use the car battery to run something it can power conveniently.

How Long Can a Circular Saw Run on a 20-Amp Car Battery?

The fact is, they do not build a car battery to run circular saws. If you try it out, the saw will only run for 5 minutes, after which it will be stone dead. It might not even cut through your material before it powers off.

Should I Choose a Cordless Circular Saw? (Corded vs. Cordless Units)

Now that you know how many watts are needed to power this saw, should you opt for a cordless unit instead?

Before making a choice, think of where you will use this tool. If it is just in a position, then your perfect choice is the corded circular saw. To make the usage more convenient, you can use an extension cord [1] or a long cord connected to the power source.

Ridgid corded circular saw

A cordless saw is your best option if your projects are in different locations. Cordless circular saw, as their name implies, are without a cord. They have a power pack that supplies the electricity needed to run the saw. 

This design makes it easy for you to move from one location to another without worrying about tangling the cord. 


What are the advantages of using a circular saw? What are its key features?

There are lots of benefits to using a typical circular saw. It is a multi-purpose power device you can use for various projects and to cut through different materials such as metal, wood, and so forth.

How do I save energy when using a circular saw?

The best way to save energy when using a circular saw is to turn it off when not in use. Also you can make use of cordless circular saws with power pack batteries.

Do circular saws experience power loss?

Yes, as with other electronic devices, they experience power loss. These losses are converted to heat. 


Now you understand how many watts does a circular saw use, you can plug it into a reliable power source without damaging the tool. It is imperative to know the wattage rating of these power tools, and their specific requirements including the blades, power type, and more to successfully craft a project.

Robert Johnson is a woodworker who takes joy in sharing his passion for creating to the rest of the world. His brainchild, Sawinery, allowed him to do so as well as connect with other craftsmen. He has since built an enviable workshop for himself and an equally impressive online accomplishment: an extensive resource site serving old timers and novices alike.
Robert Johnson
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