📐 Miter Saw Angle Calculator
Calculate precise miter, bevel, and compound cut angles for any polygon, frame, or crown molding project
| Sides | Corner Angle | Miter Cut Angle | Kerf Loss (10T @ 0.1in) | Common Use |
|---|---|---|---|---|
| 3 | 60° | 30.0° | 0.3 in total | Triangular frame |
| 4 | 90° | 45.0° | 0.4 in total | Picture frame, box |
| 5 | 108° | 36.0° | 0.5 in total | Pentagon shelf |
| 6 | 120° | 30.0° | 0.6 in total | Hexagonal planter |
| 7 | 128.57° | 25.7° | 0.7 in total | Decorative form |
| 8 | 135° | 22.5° | 0.8 in total | Octagon table, column |
| 10 | 144° | 18.0° | 1.0 in total | Decagon barrel stave |
| 12 | 150° | 15.0° | 1.2 in total | Dodecagon clock |
| Material | Blade Dia | Tooth Count | Tooth Type | Kerf Width | Max RPM |
|---|---|---|---|---|---|
| Softwood (Pine) | 10 in | 24–40T | ATB | 0.118 in | 5500 |
| Hardwood (Oak) | 10 in | 60–80T | ATB / Hi-ATB | 0.098 in | 5500 |
| Plywood | 10 in | 60–80T | Hi-ATB | 0.098 in | 5500 |
| MDF | 10 in | 60–80T | TCG | 0.110 in | 5000 |
| Aluminum | 10 in | 80T | TCG | 0.118 in | 3600 |
| PVC / Vinyl | 10 in | 40–60T | ATB | 0.098 in | 4800 |
| Cedar | 10 in | 40T | ATB | 0.118 in | 5500 |
| Laminate | 10 in | 80T | Hi-ATB | 0.098 in | 5000 |
| Spring Angle | Wall Corner | Miter Setting | Bevel Setting | Method |
|---|---|---|---|---|
| 38° | 90° | 31.6° | 33.9° | Flat on table |
| 38° | 90° | 45.0° | 0° | Spring angle against fence |
| 45° | 90° | 35.3° | 30.0° | Flat on table |
| 45° | 90° | 45.0° | 0° | Spring angle against fence |
| 52° | 90° | 38.9° | 26.3° | Flat on table |
| 38° | 135° | 22.8° | 22.1° | Flat on table |
| 45° | 135° | 25.2° | 19.1° | Flat on table |
| Project | Material | Miter Angle | Bevel Angle | Blade Rec. |
|---|---|---|---|---|
| Picture Frame | Hardwood / Pine | 45.0° | 0° | 60–80T ATB |
| Baseboard Corners | Pine / MDF | 45.0° | 0° | 60T ATB |
| Deck Board End Cap | Cedar / Hardwood | 45.0° | 0° | 40T ATB |
| Hexagonal Planter | Cedar / Pine | 30.0° | 0° | 40T ATB |
| Octagon Table Top | Plywood / MDF | 22.5° | 0° | 80T Hi-ATB |
| Crown Molding (38°) | MDF / Pine | 31.6° | 33.9° | 60T ATB |
| Window Casing | Pine | 45.0° | 0° | 60T ATB |
| Raised Panel Box | Hardwood | 45.0° | 0° | 80T Hi-ATB |
| Material | Janka Hardness (lbf) | Rec. SFM Range | Chip Load / Tooth (in) | Notes |
|---|---|---|---|---|
| Softwood (Pine) | 380–870 | 300–600 | 0.007–0.010 | Low dust, easy cut |
| Hardwood (Oak) | 1290 | 200–400 | 0.004–0.006 | Reduce RPM 10–15% |
| Plywood | — | 250–500 | 0.005–0.008 | Use fine-tooth blade |
| MDF | — | 300–500 | 0.006–0.009 | High silica dust — mask required |
| Cedar | 350 | 300–550 | 0.008–0.011 | Aromatic, prone to tearout |
| Aluminum | — (Brinell 95) | 200–400 | 0.002–0.004 | Use lubricant, non-ferrous blade |
| PVC / Vinyl | — | 150–300 | 0.004–0.006 | Slow feed to prevent melting |
| Hardwood (Maple) | 1450 | 150–350 | 0.003–0.005 | Very hard — fine-tooth blade |
Miter Saw commonly confuses folks when dealing with corners, and just understanding the number already helps a lot. On paper, a 90-degree corner one designs directly. But to cut a 90-degree corner with a Miter Saw you must set it to 0 degrees.
Here start the troubles. On the other hand, for 45 degrees the results match in both cases, because the systems then match. The same happens at table saws: if the Miter Saw scale stands at 30 degrees, that indeed gives a 60-degree cut on the wood.
How to Get Correct Corners with a Miter Saw
Miter Saws can confuse even expert carpenters, because they were not really meant for final woodworking. They were designed mostly for trim work and staircases. They simply ended up used for installation.
A normal straight cut has a bevel at 0 degrees. Most saws reach a maximum bevel of 45 degrees. The Miter Saw Angle shows the horizontal turn on the table of the saw, measured form the line straight to the long side of the board.
When you turn the board on its edge and press it to the fence, you cut a bevel. Most saws allow cuts from 90 to 45 degrees in both directions, and some even to 55 degrees.
Basic Miter Saws cut only in one plane. But most are combined Miter Saws, that work in two planes. The saw twists to the write and to the left and tilts from upright position to usually around 45 degrees.
Some have tilt only one way, which is called single bevel.
Do not assume that the Angle is exactly 90 degrees. Measure the real Angle with a bevel gauge, then set the Miter Saw to half of that number. Materials commonly are not perfectly straight, so you must fix the corners.
When you cut octagons, set the saw to 22.5 degrees, do test cuts on scrap pieces and make sure that they meet at 90 degrees when you glue them and press to a straight frame. Change the exact Angle if they do not match.
Calibration is another common problem. On some saws the Angle locking screws do not hold in spot. That is part of the design.
During setup of any Miter Saw, the default position does not always match a real 90-degree cut. The user must check and correct it. Digital Angle gauges help and usually store settings for 45 and 90 degrees on the saw.
Check the manual to know how to change the stop points; there should be bolts in the half-turn plate that marks the corners. All Miter Saws need setup, andthe best have stop systems that you can fix.
Lasting perfect miters are harder than many believe. Perfectly flat and straight material, together with a well set saw and good blade, makes a big difference.
