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

Tenon Length Millimeters (mm)

Required number input.

Glue Relief Millimeters (mm)

Required number input.

Equal mortise depth in each member for a centered floating tenon, plus a specified glue-relief allowance. 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]

Mortise Depth Millimeters (mm)

The resulting mortise depth millimeters 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.

• Domino Routing Depth Calculator

  Compute the mortise depth for a centered Domino loose-tenon joint. Each workpiece normally receives half the nominal tenon length; verify the joiner's available depth-stop setting, especially for the 4 x 20 mm Domino.

• Mortise Depth

  Specify mortise depth for a given tenon length plus a deliberate end-clearance allowance for glue or debris.

• Biscuit Slot Depth

  Target insertion depth on each side of a centered biscuit joint from biscuit width plus a chosen glue clearance.