📐 Most Common Cuts
⚠️ Before you cut — check these two things:
- Spring angle: Check your molding label — most store-bought is 38° (labeled "52/38")
- Corner angle: Measure with a digital angle finder — don't assume 90°
Standard
Inside Corner · 90°
38° spring angle · flat cut on saw table
Miter · Bevel
31.62° · 33.85°
Outside
Outside Corner · 90°
38° spring · ceiling edge against fence
Miter · Bevel
31.62° · 33.85°
Common
Inside Corner · 88°
Slightly acute — very common in older homes
Miter · Bevel
30.86° · 33.18°
Common
Inside Corner · 92°
Slightly obtuse — very common in newer homes
Miter · Bevel
32.37° · 34.51°
45° Spring
Inside Corner · 90°
45° spring angle (45/45) · flat cut
Miter · Bevel
35.26° · 30.00°
52° Spring
Inside Corner · 90°
52° spring angle (38/52) · flat cut
Miter · Bevel
38.24° · 25.81°
📏 Identify Your Spring Angle
How to find it in 30 seconds
Check the label — look for "52/38" or "45/45" on the packaging or end of the molding. The second number is your spring angle.
Method 1
Lay flat & measure — place molding back-side up on a flat surface. Measure the angle between the back flat and the table surface. That's your spring angle.
Method 2
When in doubt: most crown molding at Home Depot and Lowe's is 38° spring angle. Try 38° first.
Quick tip
📊 Non-90° Corner Reference · 38° Spring
| Corner Angle | Miter | Bevel |
|---|---|---|
| 85° | 29.42° | 31.78° |
| 87° | 30.14° | 32.48° |
| 88° | 30.86° | 33.18° |
| 90° ⭐ Standard | 31.62° | 33.85° |
| 92° | 32.37° | 34.51° |
| 95° | 33.63° | 35.49° |
| 100° | 35.89° | 37.38° |
| 110° | 40.59° | 40.33° |
| 120° | 45.00° | 42.43° |
| 135° | 51.34° | 44.44° |
For any corner angle → use the free calculator at crownmoldingangles.github.io
🪚 Flat Cut · Molding Position on Saw
Inside corner — molding flat on saw table
❌ 3 Most Common Mistakes
Assuming 90° — Most corners measure 88°–92°. Even 1° off creates a visible gap once painted. Always measure with a digital angle finder before cutting.
Wrong spring angle — Using 38° settings on 45° molding produces cuts that look almost right but fit terribly. Check your molding label before anything else (look for "52/38" or "45/45").
Outside corner orientation — For outside corners, the ceiling (top) edge goes against the fence — opposite of inside corners. This trips up even experienced DIYers.
✅ Get Angles for Any Corner
1
Measure your corner with a digital angle finder — don't assume it's 90°. Most walls are off by 1–3°.
2
Find your spring angle — check the molding label. Most store-bought crown is 38°.
3
Enter both numbers at crownmoldingangles.github.io — get exact miter & bevel settings instantly. Free, no signup.
4
Cut a test piece in scrap first. Verify the fit before cutting your good molding.
📚 Related Guides
Spring Angle Guide
Identify 38°, 45°, and 52° in 30 seconds
Outside Corners
Exact angles and saw orientation
Non-90° Corners
Angles for walls that aren't square
Full Angle Chart
Every corner 85°–135°, all spring angles
Coping vs Mitering
Which technique pros use for inside corners
Vaulted Ceilings
Special angles for sloped ceilings