Joints & Joinery Calculators
Calculate dimensions and spacing for dovetails, mortise and tenon, box joints, dowels, and other woodworking joints.
Dovetail Calculator
Calculate dovetail pin and tail spacing for hand-cut or machine joints.
Mortise and Tenon Calculator
Work out mortise and tenon dimensions based on timber size.
Box Joint Calculator
Calculate finger joint spacing and dimensions for box construction.
Dowel Spacing Calculator
Determine optimal dowel positions and spacing for edge joints.
Biscuit Joint Calculator
Calculate biscuit size and spacing for panel and edge joints.
Pocket Hole Calculator
Determine pocket hole screw size and spacing for face-frame joinery.
Bridle Joint Calculator
Calculate bridle joint dimensions for frame construction.
Lap Joint Calculator
Work out lap joint dimensions and material removal for frame joints.
Tongue and Groove Calculator
Calculate tongue and groove dimensions for panel and flooring joints.
Spline Joint Calculator
Determine spline dimensions and groove depth for reinforced mitre joints.
10 free calculators in Joints & Joinery
Woodworking Joint Calculations
Joinery is the heart of fine woodworking. Getting joint dimensions right first time means tight-fitting, strong connections that will last for generations. These calculators help you work out the precise dimensions for all common woodworking joints.
Dovetails are the hallmark of quality craftsmanship. The traditional ratio is 1:6 for softwoods and 1:8 for hardwoods, giving an angle between 7° and 10°. Our dovetail calculator spaces pins and tails evenly across the board width, accounting for half-pins at each edge.
The mortise and tenon is arguably the strongest woodworking joint. The standard rule is that the tenon thickness should be one-third of the stock thickness, with the tenon length equal to two-thirds of the mortise piece width. Our mortise and tenon calculator works out all dimensions automatically based on your timber sizes.
Modern joinery methods like biscuits, pocket holes, and dowels offer speed and convenience for production work. Our calculators determine the correct sizes and spacing to ensure strong, reliable joints every time.