Baseboard Trim Calculator

About this calculator

This calculator adds up a room's wall perimeter, subtracts the width of door openings (baseboard doesn't run across a doorway), then adds a waste allowance — typically 10% — to cover cut losses and mistakes, and finally divides the total by the standard trim length sold at lumber yards (often 2.4 m or 8 ft) to give the number of pieces to buy.

Contractors and DIY renovators use it to order the right amount of skirting board before a job rather than guessing and making multiple trips to the store, since baseboard is typically sold in fixed lengths and running short mid-installation means matching a stain or finish on a second trip.