Baseboard Calculator
How many pieces of baseboard trim
Installing baseboard or trim? Enter the room perimeter to find the linear feet and number of pieces you'll need.
Measuring for baseboard
Add up the length of every wall (the perimeter), then subtract door openings. Buy in standard 8-foot or 16-foot lengths and add ~10% for miter cuts and mistakes.
Inside vs. outside corners
Inside corners are best "coped" — one piece is cut to nest against the profile of the other — which hides gaps better than a miter when walls aren't perfectly square. Outside corners (around a chimney chase or closet) are mitered. Count your corners when buying: each one is a cut that consumes a little length.
Buy longer pieces and pre-finish
On walls longer than a single board, use the longest lengths you can carry to minimize seams; joints in the middle of a long wall are hard to hide. Prime and paint the baseboard before installing for a cleaner finish, then just touch up the nail holes and seams afterward.
Baseboard Calculator: frequently asked questions
How do I measure for baseboard?
Measure the perimeter of the room, subtract doorway widths, and add ~10% for cutting waste.
What lengths does baseboard come in?
Commonly 8, 12 and 16-foot pieces; longer pieces mean fewer seams on long walls.
Should baseboard corners be coped or mitered?
Cope inside corners — it gives a tight joint even when walls are out of square — and miter outside corners. Most rooms have far more inside corners, so coping is the skill that makes baseboard look professional.