Miter angle chart
The saw setting for a flat frame or ring of any number of sides, and for a corner that is not square. Every angle here is one cut on one end of one piece.
Not on the chart? Work out your own: Miter angle calculator →
| Sides | Shape | Interior angle | Miter per end | Cuts in the job |
|---|---|---|---|---|
| 3 | Triangle | 60.0° | 60.0° | 6 |
| 4 | Square | 90.0° | 45.0° | 8 |
| 5 | Pentagon | 108.0° | 36.0° | 10 |
| 6 | Hexagon | 120.0° | 30.0° | 12 |
| 8 | Octagon | 135.0° | 22.5° | 16 |
| 10 | Decagon | 144.0° | 18.0° | 20 |
| 12 | Dodecagon | 150.0° | 15.0° | 24 |
| 16 | 16-sided | 157.5° | 11.3° | 32 |
| 24 | 24-sided | 165.0° | 7.5° | 48 |
Reading it
- The miter per end is 180 ÷ sides. A square frame is 45°, a hexagon 30°, an octagon 22.5°.
- This is the flat case — pieces lying in one plane. A ring whose staves lean inward is a compound miter and needs a bevel too; that is the segmented ring calculator.
- Error multiplies by twice the number of joints. A twelve-sided ring with every cut 0.1° over leaves 2.4° of the 360° unaccounted for, which is a visible gap.
- For a corner that is not one of these, the miter is (180 − the corner you measured) ÷ 2.
For the case this table does not cover
- Miter angle calculator
The miter for baseboard, casing or chair rail at any corner angle — flat trim, so there's no bevel to set.
- Hexagon and octagon calculator
Side length, across flats and across corners from any one of them, for any regular polygon, with the area, the miter and each frame piece's cut lengths.
- Segmented rings and columns
Miter and bevel for any number of sides, flat or flared, and how long each segment has to be.
- Picture frame miter cuts
Cut lengths, long point to long point, for a rectangular mitered frame, and how much molding to buy.