How to Use Angle Cut Calculator
The Angle Cut Calculator answers the everyday “what angle do I cut?” question.
- Enter the corner angle — The angle the two pieces will form when joined (90° for a square corner, 135° for an octagon).
- (Optional) Enter board width — Useful for cross-checking long miters or scribe layouts.
- Read the result — Per-piece miter angle (θ / 2), saw setting (90° - θ / 2) and full corner angle.
Formula & Theory — Angle Cut Calculator
The Angle Cut Calculator uses one elementary identity:
Per-piece miter = θ / 2
Saw setting = 90° - θ / 2
Two-piece joint = 2 × per-piece miter = θ| Symbol | Meaning |
|---|---|
| θ | Included corner angle |
| Saw setting | Angle dialled in on a miter saw |
For polygons, θ = 180° × (n - 2) / n where n is the number of sides.
Compound cuts
For sloped frames (crown moulding, hopper boxes), miter and bevel must both be set. The Angle Cut Calculator gives the miter component; for compound bevels, see specialist trim references.
Use Cases for Angle Cut Calculator
- Picture framing — Mitre corners for picture and mirror frames.
- Trim carpentry — Cope and miter baseboard, crown and casing.
- Decking — Cut angled deck boards around obstructions.
- Polygon tables — Determine cuts for hexagonal, octagonal and other regular shapes.
- Stair stringers — Lay out angled stringers and tread junctions.
- Education — Reinforce the corner / per-piece relationship for woodworking students.
The Angle Cut Calculator removes guesswork from miter saw setup and keeps joints tight.