Compound Miter Calculator

Compound Miter Calculator is the complete tool for woodworkers, carpenters, and serious DIYers who need precise compound angles for sloped, tilted, or many-sided projects.

Whether you are cutting crown molding, gluing up a segmented turning blank, staving a tapered cone or planter, or framing a tilted shadow box, this app does the trigonometry for you and gives you a fold-over template you can wrap around the wood.

WHAT IT CALCULATES

Enter the number of sides (or a flat miter angle) and the side angle from horizontal. The app instantly returns:

- Miter Angle - the angle to set on your saw

- Bevel Angle - the blade tilt

- Flat-miter angle and intermediate values for reference

LIVE DIAGRAMS

Every diagram updates as you type:

- Fold-over template with fold lines and labels

- Flat miter angle illustration

- Miter and bevel protractors

- 2D cone side view sized to your project

ACTUAL-SIZE PRINTABLE TEMPLATES

Export a PDF with a one-page summary of inputs, results, and diagram previews, plus a multi-page 1:1 scale fold-over template tiled across US Letter or A4 sheets, complete with crop marks and alignment guides. Tape the pages together, fold the template over the work, and trace your cut lines directly onto the wood. No math at the bench.

INCHES OR MILLIMETRES

Switch units anytime. Imperial input uses fast wheel pickers for whole inches and 16ths so you can dial in fractions the way you read your tape. Metric input accepts decimals with either a comma or a dot, so it works wherever you are.

PROJECTS YOU CAN BUILD

- Crown molding and trim with any wall slope

- Segmented turning blanks and lathe bowls

- Staved cones, planters, and buckets

- Tilted picture frames and shadow boxes

- Speaker cabinets and hoppers

- Pyramids, lampshades, and tapered boxes

MADE FOR iPhone AND iPad

Clean layout with large readable angle results, collapsible diagram cards, and a two-column iPad mode. A Done button on every keyboard, smart input handling, and your last-used values are remembered between launches.

EXPORT AND SHARE

- Plain-text summary for email or messages

- High-resolution PDF for printing or your shop computer

- Standard iOS share sheet built in

OFFLINE AND PRIVATE

Runs entirely on your device. No sign-up, no tracking, no internet required.

Stop second-guessing your saw setup. Get the angle right the first time, and walk into the shop with a template that actually fits.