Baseboard / Trim Calculator
Calculate how much baseboard or trim you need based on room perimeter, accounting for doors and windows.
Trim Needed
Baseboard/trim length is calculated by measuring the room perimeter and subtracting openings where trim is not installed.
Trim Needed = Room Perimeter - (Door Widths + Window Widths)
Standard door widths to subtract:
- Interior door: 3 ft (0.9 m)
- Double door: 6 ft (1.8 m)
- Sliding glass door: 6 ft (1.8 m)
Standard window widths to subtract (baseboard only):
- Windows typically do NOT reduce baseboard unless they extend to the floor
Baseboard is sold in lengths of:
- 8 ft, 10 ft, 12 ft, or 16 ft pieces
Tips:
- Add 10-15% for waste, cuts, and mitering corners
- Each inside/outside corner wastes a few inches
- Buy all trim from the same lot for consistent color/grain