The miter saw is the most-used trim tool in residential carpentry and one of the most useful in a furniture shop. The naming of its cuts gets confused constantly, even on construction sites. A miter cut is not the same as a bevel cut, a compound cut is a combination of both, and getting the names wrong leads to wasted lumber and trim that does not close at the corner. Here is the plain version of what each cut is, when to use it, and how to set the saw correctly.
The four cut types
A miter saw makes four fundamental cut types, defined by which axis the blade rotates around.
A crosscut is a square cut: the blade is at 0 degrees miter and 0 degrees bevel. The cut goes straight through the board perpendicular to both the long axis and the face. This is the most common cut and what every miter saw does at default settings.
A miter cut rotates the blade left or right relative to the fence. The blade tilts around a vertical axis, so the cut line on the face of the board angles away from 90 degrees. Common miter cuts are at 45 degrees (for a 90-degree corner joint) and 22.5 degrees (for octagonal frames). The blade is still vertical, only its rotation in the horizontal plane changes.
A bevel cut tilts the blade forward or backward toward the workpiece. The blade angles around a horizontal axis, so the cut line through the thickness of the board angles away from 90 degrees. Common bevel cuts are 45 degrees (for cutting deck-board ends at an angle) and 22.5 degrees (for spliced joints in beams). The blade rotation in the horizontal plane stays at 0 degrees.
A compound cut combines a miter and a bevel in the same pass. The blade is both rotated and tilted. The most common compound cut is the crown molding cut for an inside 90-degree corner: 31.6 degrees miter and 33.9 degrees bevel for 38-degree spring crown laid flat on the saw table.
Why the names matter
Trim carpenters argue about cut names because the wrong name produces the wrong cut. A request for “a 45 miter on this baseboard” is unambiguous and produces a corner joint. A request for “a 45 bevel on this baseboard” produces a board with a long-tapered end that will not close into a corner. The two cuts look similar on a single board but combine differently.
In casework, the same distinction applies. Mitered casework corners (where two boards meet at a 45-degree miter at the corner) use miter cuts. A bevel cut on the same boards would produce a beveled edge along the corner, useful for chamfered details but not for a clean miter joint.
In compound work like crown molding, the miter and bevel both have to be correct simultaneously. The numbers come from the molding’s spring angle (the angle the molding sits at when installed) and the corner angle (typically 90 degrees, sometimes 135 for bay windows). Look up the settings on a crown molding chart or use the saw’s built-in detents for the standard 38-degree and 45-degree spring profiles.
Setting up miter cuts
Every miter saw has a miter scale that reads from 0 degrees (perpendicular) to 45 or 50 degrees in both directions. The scale is on the rotating table base. Most saws have positive detents at 0, 15, 22.5, 31.6, 45, and 50 degrees, which lock the table at those common angles.
For a 45-degree miter on a piece of trim, rotate the table to the 45-degree detent on either the left or the right side, depending on which end of the trim you are cutting. The miter scale reads the angle of the cut line relative to the fence. A 45-degree miter cuts a 45-degree angle into the face of the board.
For a non-standard angle, release the detent and rotate the table to the exact reading on the scale. The scale resolution on most consumer saws is 0.5 degrees. Production saws with vernier scales read to 0.1 degree.
Check the miter calibration once a month with a machinist’s square. Place the square against the fence and the blade in the 0-degree position. There should be no gap between the square and the blade. If there is, adjust the fence-to-blade angle using the calibration screws under the table. A saw that drifts 0.5 degrees off square will produce mitered corners that do not close.
Setting up bevel cuts
Every miter saw has a bevel scale that tilts the entire saw head left (and right, on dual-bevel saws). The scale reads from 0 degrees (vertical) to 45 or 47 degrees. Most saws have positive detents at 0, 22.5, 33.9, and 45 degrees.
For a 45-degree bevel, tilt the saw head to the 45-degree detent on either side (dual-bevel saws only) or only on the left (single-bevel saws). A single-bevel saw can still make right-leaning bevels, but you have to flip the workpiece end-for-end to make the cut.
The bevel scale typically reads 1 degree resolution. Calibrate the bevel by placing a square against the saw table and the side of the blade at 0 degrees. There should be no gap. Adjust with the bevel calibration screws if needed.
Compound cuts and crown molding
Compound cuts are where most people get confused. The standard residential crown molding profile in the United States is 38-degree spring angle. The molding sits against the wall and the ceiling at 38 degrees from vertical. Two pieces of this molding meeting at an inside 90-degree corner need each cut at 31.6 degrees miter and 33.9 degrees bevel.
To make this cut on a saw with crown detents, set the miter to 31.6 degrees (the saw will click into the detent) and the bevel to 33.9 degrees (also detented on most saws). Lay the molding flat on the saw table with the ceiling-side edge against the fence. Cut. The piece for the other side of the corner gets the opposite miter direction.
The cuts can also be made nested, with the crown standing up against the fence at the spring angle. Nested cuts use only the miter (45 degrees for a 90-degree corner) and no bevel, which is simpler but requires a saw deep enough to accommodate the molding standing up. Most 10 inch saws handle up to 4.5 inch nested crown, most 12 inch saws handle up to 5.5 inch nested crown.
For inside corners, the cut goes through the back face of the molding so the visible face is the long point of the cut. For outside corners, the cut goes through the front face so the visible face is the short point. Get this wrong and the corner will not close.
Common mistakes
Cutting on the wrong side of the line: trim is cut to length, so the offcut is waste. Always position the saw blade on the waste side of the layout line, not on the layout line. A 1/8 inch error from cutting on the wrong side will be visible at the corner.
Mixing inside and outside cuts: inside corners and outside corners use opposite miter directions for the same wall position. Mark the back of each piece with an arrow pointing toward the corner before cutting.
Cutting all four pieces at once and assembling at the end: never. Cut one corner, test fit it, then cut the next. Lumber is slightly inconsistent, walls are not always 90 degrees, and a small adjustment at piece 2 saves a wasted piece 4.
See our methodology page for the trim and joinery tests we run. A miter saw is mostly a calibration and a workflow tool. Once the saw is square and the cut names are clear, the work goes fast.
Frequently asked questions
What is the difference between a miter cut and a bevel cut?+
A miter cut rotates the saw blade left or right relative to the fence. The cut angle is in the horizontal plane (looking down at the workpiece). A bevel cut tilts the saw blade forward or backward toward the workpiece. The cut angle is in the vertical plane (looking at the workpiece from the side). A miter changes the angle across the face of the board, a bevel changes the angle across the thickness of the board. Both can be set to anything between 0 and 45 to 50 degrees on most saws.
What is a compound cut?+
A compound cut is a miter and a bevel made simultaneously in the same pass. Crown molding installed on a flat saw table requires compound cuts because the molding sits against the fence at the wall angle and has to be cut both across its face (miter) and through its thickness (bevel) to meet the next piece at the corner. Most modern 10 inch and 12 inch miter saws support compound cuts up to 50 degrees miter and 47 degrees bevel.
Do I need a sliding miter saw for crown molding?+
Only for crown wider than about 4.5 inches when cut flat on a 10 inch saw, or 6 inches on a 12 inch saw. Smaller crown can be cut nested (stood up against the fence at the spring angle) on any miter saw. Most residential crown is 3.5 to 5.25 inches and works fine on a non-sliding 12 inch saw. The slide is useful for wide base molding (6 to 7 inches), wide trim boards, and deep cuts in 4x4 stock.
What miter and bevel settings cut a standard 90 degree corner in crown?+
For 38 degree spring angle crown (the most common American profile) cut flat on the saw table, the settings are 31.6 degrees miter and 33.9 degrees bevel. These are the same on every saw and are usually marked with detents. For 45 degree spring crown the settings change to 35.3 degrees miter and 30 degrees bevel. The exact numbers come from the spring angle of the molding profile, which the manufacturer prints on the box.
Why is my miter cut leaving a thin gap at the heel?+
Either the saw is slightly out of square (the blade is not at 0 degrees when the indicator says it is), the workpiece is shifting during the cut, or the wood is cupped. Check square with a machinist's square against the blade and the fence. Adjust the fence-to-blade angle using the saw's calibration screws if needed. Use a hold-down clamp on long pieces. If the wood is cupped, cut with the convex side against the fence so the cut closes when assembled.
