Dowel Spacing Calculator
Dowel joints fail in predictable ways: too far apart and the joint twists, too close to the edge and the wood splits. This lays out a proper grid for any panel size and dowel diameter.
1/4, 3/8 or 1/2
Results
Enter your measurements above and press Calculate.
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Questions people ask
How far apart should dowels be spaced?
No more than twice the dowel diameter. For ⅜ inch dowels that is ¾ inch center to center. Wider spacing weakens the joint because the panels can flex between holes.
What size dowel should I use?
Half the thickness of the thinner panel is the traditional rule. Two ¾ inch panels take ⅜ inch dowels; two 1 inch panels take ½ inch. Dowels must be at least 2 inches long to get enough glue surface.
Do I need glue with dowels?
Yes — yellow woodworking glue, and it must be applied to both pieces. Dowel joints with no glue have almost no strength, and the fit alone is what creates the alignment advantage.
Should I use fluted or straight dowels?
Fluted dowels let excess glue escape and are the right choice for glue joints. Straight dowels are for pin joints or joinery where you want full contact. Use hardwood dowels; pine dowels are too soft and split.
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