Lap Joint Calculator — Overlap Joint Dimensions
Calculate lap joint dimensions and material removal for half-lap, full-lap, and dovetail-lap joints.
How We Calculate This
This calculator determines the notch dimensions for lap joints.
Half lap
Each piece is notched to half its thickness. The notch width equals the width of the mating piece.
Full lap
One piece is notched to the full thickness of the other, which sits in the notch uncut.
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates. Always verify measurements and material quantities before cutting or purchasing.