Use this workshop calculation to turn measured dimensions and the selected construction convention into a cut, spacing, fit, or material-planning value.

Panel thickness (mm)

Required number input.

Total clearance (mm)

Required number input.

Allow a dado to fit a measured panel thickness with explicit total width clearance. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Cut width (mm)

The resulting cut width returned as a number.

• Nominal dimensions, kerf, moisture movement, hardware clearances, wall squareness, and manufacturer instructions can change the required shop dimension. Measure the actual assembly and test critical joints on scrap before cutting finished material.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Complement the calculated dimension with a physical story stick, dry fit, or full-size layout. Follow the hardware, coating, adhesive, or machine manufacturer's limits where they differ from a rule of thumb.

• Tongue Thickness

  Find tongue thickness from mating groove width after subtracting an explicit total fit clearance.

• Inlay Strip Width

  Set inlay-strip cut width from a measured groove width after subtracting a chosen total fit clearance.

• Mortise Width

  Size mortise width to receive a measured tenon thickness plus chosen side-to-side fit clearance.