How To Make A 90 Degree Cut With A Circular Saw

As an Amazon Associate we earn from qualifying purchases.

A circular saw is a potent tool to make perfect square and straight cuts. But without using proper techniques and steps, making these cuts can be dangerous. So here is a complete guide on how to make a 90 degree cut with a circular saw safely and accurately.

How To Make A 90 Degree Cut With A Circular Saw

Follow the steps mentioned below to quickly learn how to make a 90 degree cut with a circular saw very efficiently.

Step #1: Unplug the Saw and Install the Blade

The first and the most crucial safety step to follow before adjusting your saw is to make sure that the circular saw is unplugged.

After ensuring that, you need to check if you have installed the right blade depending on the material you want to cut and the purpose of the cut.

Man holding a circular saw

The same tool can cut through either concrete or plywood , but it can only do each job if it has the right blade installed in it.

Different types of saw blades can do different kinds of cuts on different materials. Some examples of circular saw blades types include:

  • Woodcutting blades
  • Masonry cutting blades
  • Metal cutting blades
  • Plastic pipe cutting blades

Step #2: Set the Angle of the Blade

The next step is to set the pitch or the angle of the blade. To set the angle, first, check the point at which the angle lever attached at the front of the circular saw is marked. The angle lever has markings from 0 to 45.

So for a 90-degree cut, the marking should be precisely at the 0 mark. If it is not, you can loosen the lever, set the marker at 0 on the label plate, and secure it.

After doing this, you must double-check it with the help of a speed square, also known as rafter square or rafter angle square.

Take your saw and flip it upside down, set the speed square against the saw guard, and check for any gaps between the blade and the saw. If there are no gaps, then it is good to go.

Step #3: Set the Depth of the Saw

The next step is to set the depth or the length of the saw.

And to execute this successfully, you must ensure that the saw blade is about ⅛th of an inch past the wood.

If not, try loosening up the base plate attached with a screw at the back. Then you can easily set the length accordingly.

After setting the length or the depth, always make sure to tighten the screw. Finally, plug the saw back in.

Step #4: Mark the Measurements and Clamp the Wood

Marking accurate measurements is the most crucial part of this whole process. If this step goes wrong, you might end up cutting the wood incorrectly.

Man marking a piece of wood

So to measure, use a tapeline and a sharp carpenter pencil and try marking the point with a “V.” It helps note the exact point, which is the intersection of both the lines.

Then, draw a straight line connecting the points with the help of a speed square.

After taking the measurements, you should clamp your wood, ideally one at the end of the wood piece and one at the opposite side so that it stays in place without sliding out.


Making super accurate cuts with a circular saw is a tricky business. So always make sure to make your marking on the waste side of the measurement so that you can quickly and easily line up the guide to the edge of the mark. Doing this can help make an exact cut easily without reducing the required length of the wood.

Step #5: Cut the Wood

The final step after setting up the circular saw is to cut the wood. Place the tip of the base plate on the piece of the wood that you wish to cut.

The base plate should sit at the exact level on the wood, and the blade should point downwards. After this, without making contact with the wood, pull the trigger, hold it and let the blade spin at maximum.

Once the blade is at full speed, push the saw towards the wood. Glide the base plate of the saw properly across the body of the wood, making the blade cut through the wood.

Then once you reach the end, the part of the wood that you just cut will fall off on the ground. After which, you can release the trigger and bring the saw blade to rest.

To understand these steps more clearly, here is a video illustrating how to make a 90 degree cut with a circular saw.

Important Safety Precautions

A circular saw is a very convenient tool but can also be relatively hazardous if used improperly. So it is vital to take the necessary safety precautions.

You should always wear woodworking gloves, safety goggles, work pants, and ear muffs to provide complete protection to your hands, eyes, legs, and ears.

Circular saw

And if you are an amateur and have no idea how a circular saw works, always check the user manual thoroughly before using it.

Moreover, you should never try to bind the blade during the cut. Doing this can make the blade slide off and rush backward at you.

Frequently Asked Questions

How to Avoid Splintering While Cutting with a Circular Saw?

You can easily avoid splintering while cutting with a circular saw by adding a zero clearance plate to the bottom of your saw. But it is necessary to ensure that the circular saw’s base plate is held tightly to the workpiece for this to work.

Or the next best alternative can be to mark along the cut line with a utility knife. This practice helps sever the fibers, and when the saw blade cuts through it, the surface fibers won’t splinter.

How to Prevent Saw Blade Burns on Wood?

To prevent the saw blade from burning on wood, use a sharp, clean, and free of pitch blade. Then adjust the blade alignments correctly by referring to the user’s manual. Lastly, make sure to choose a blade with the perfect feed speed.

How to Prevent Circular Saw Kickbacks?

Usually, kickbacks occur because of improper setting of depth and faulty cuttings. So for a good cut, it is necessary to make sure to set up the blade at the right angle and adjust the depth of the saw properly.

You should also correctly clamp the wood on both ends to immobilize it and give it proper support. By following these steps precisely, you can prevent substantial circular saw kickbacks to a great extent.


Using a circular saw to cut through any material is tricky, but it becomes effortless once you get the hang of using the tool properly. It is a very efficient tool that can help provide cleaner and more precise cuts than a traditional saw.

The whole cutting process in different angles and measurements becomes way more manageable and swifter when using a circular saw. But it is also essential to buy a good quality tool and the best preventive gear to ensure maximum safety.

An expert at home repair, remodel, and DIY projects for nearly 40 years. His first experience came in completely restoring an antique home. Completely redone from the inside out, and restored to its original form, the home is a featured design by renowned Southern California Architect Cliff May, considered to be the father of the California Ranch Home. Now Dennis spends his time on fine woodworking projects and tool comparisons.