Crown Molding Angle Calculator

The crown molding angle calculator takes your wall corner angle and the molding's spring angle, then returns the compound miter and bevel saw settings. For a 90° corner with 38° spring crown, the result is about 31.62° miter and 33.86° bevel.

Last reviewed September 2026Method & sources Report an error

Not to scale.

Saw Miter Angle

31.62 °

Breakdown
Saw Miter Angle	31.62°
Saw Bevel Angle	33.86°

How to Calculate Crown Molding Angle

Crown molding sits at an angle (the spring angle) between the wall and ceiling instead of lying flat. So a corner cut needs two saw settings at once: a miter (table rotation) and a bevel (blade tilt). Flat trim needs only the single miter angle. This calculator projects the molding's spring angle onto the saw's two axes using the standard compound-angle formulas (miter = atan(sin(spring angle) × tan(corner angle ÷ 2)), bevel = asin(cos(spring angle) × cos(corner angle ÷ 2))). It assumes the common method of cutting the molding lying flat on the saw table, upside down and backwards, against the fence. It works for any corner angle and any spring angle. That goes beyond the standard 90° corner and 38°/45° spring angles most printed charts stop at. Those two spring angles still cover the large majority of crown molding actually sold.

Example: Standard 90° square corner, using 38° spring-angle crown molding

A standard 90° square corner, using 38° spring-angle crown molding: 1. Half the corner angle: 90° ÷ 2 = 45°. 2. Miter angle: atan(sin(38°) × tan(45°)) = atan(0.6157 × 1) ≈ 31.62°. 3. Bevel angle: asin(cos(38°) × cos(45°)) = asin(0.7880 × 0.7071) ≈ 33.86°. Set the saw's miter to 31.62° and bevel to 33.86°, with the molding lying flat on the table upside down and backwards against the fence. The same 90° corner in 45° spring-angle crown instead: miter ≈ 35.26°, bevel = 30.00° exactly.

What Is Crown Molding Angle?

A crown molding angle calculator converts a wall corner's angle and the molding's spring angle into the miter and bevel settings a compound miter saw needs to cut a clean corner joint. The spring angle is how far the profile leans between the wall and ceiling. This is the two-number compound cut that trips up more DIYers than any other trim detail, since crown can't be cut flat like baseboard or casing.

Crown Molding Angle: Pros and Cons

Pros

Works for any corner angle, not only the standard 90° corners most printed compound-angle charts list
Also works for any spring angle, not only the two most common values (38° and 45°), for a specialty or historical molding profile
One formula covers both the miter and bevel setting together, instead of needing a separate chart lookup for each

Cons

Assumes the molding is cut lying flat on the saw table, upside down and backwards against the fence. That is the common method. A compound miter saw with a tilting table and a crown-molding stop can cut it standing upright instead, which uses different settings this calculator doesn't cover
Doesn't measure your actual corner angle or your molding's actual spring angle for you. An out-of-square corner should be measured directly. The spring angle should be checked against the molding's own packaging or profile, since 38° and 45° aren't the only spring angles ever sold
Always make a test cut on scrap first. Saws label miter/bevel direction (left/right, positive/negative) differently, and it's far cheaper to waste a scrap offcut than a full length of crown molding

Crown Molding Angle: What a Pro Checks

Measure your actual corner with a protractor or angle finder before cutting. Very few real corners are exactly 90°. This calculator's whole advantage over a printed chart is that it adjusts for the corner you actually have.
Check your molding's spring angle on the packaging or by measuring it directly. 38° and 45° cover most commercial crown, but a specialty or historical profile can differ.
Cut one test joint on scrap before touching your real molding. Miter and bevel direction (left/right, positive/negative) isn't labeled the same way on every saw.

Frequently Asked Questions

What are the miter and bevel settings for 38° crown molding on a 90° corner?

About 31.62° miter and 33.86° bevel, with the molding lying flat on the saw table upside down and backwards against the fence. It is the most commonly cited compound-angle setting for standard 38°-spring crown molding at a square corner.

What are the miter and bevel settings for 45° crown molding on a 90° corner?

About 35.26° miter and exactly 30.00° bevel. That is the standard setting for 45°-spring ("45/45") crown molding at a square corner, a different pair of numbers from 38°-spring crown at the same corner.

Why does crown molding need both a miter angle and a bevel angle?

Because crown molding is installed at a spring angle, tilted between the wall and ceiling rather than lying flat against one surface. Flat trim (baseboard, casing) only needs a miter angle, since it's cut standing in the same plane it's installed in. Crown's tilt means the saw also needs to tilt (the bevel) to reproduce the corner correctly.

Does this work for a corner that isn't 90°?

Yes. Enter the actual corner angle (measured with a protractor or angle finder), and the calculator recomputes both the miter and bevel settings for that specific angle. A printed chart typically only covers a few standard corners.

Are there crown molding spring angles other than 38° and 45°?

Those two cover the large majority of crown molding sold. Specialty, historical, or custom-milled profiles can use a different spring angle. Check your molding's packaging, or measure the angle between its back face and a flat surface directly. Then enter that value instead of assuming 38° or 45°.

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