How much baseboard do you need?
Add your rooms or walls, get linear feet and pieces of baseboard instantly.
How do I calculate how much baseboard I need?
Add up the length of every wall — for a rectangular room that is 2 × (length + width) — and subtract the width of each doorway. Add 10% for the miter cuts at corners. A 12 by 12 ft room with one 3 ft doorway needs 48 − 3 = 45 feet; with 10% extra that is 49.5 feet — seven 8 ft pieces or four 16 ft pieces.
Should I buy 8, 12 or 16 ft baseboard?
Longer pieces mean fewer seams: a 14 ft wall is one 16 ft piece but two 8 ft pieces with a joint in the middle. Shorter pieces are easier to carry and fit in a car. Enter the prices of each length and the calculator marks the cheapest way to buy.
How much extra baseboard should I buy?
About 10% for a simple room. Every inside and outside corner costs a little at the miter, and pieces rarely come out even — add 15% for rooms with many corners, bay windows or closets.
Do I subtract doorways from baseboard length?
Yes — baseboard stops at the door casing, so take off each doorway: about 3 feet for a standard door. Leave in openings that get baseboard around them, such as an archway with trim returning into it.
How do I measure a room with closets or odd walls?
Measure the room as a rectangle and add each closet or alcove as a separate run with the length of its walls. For stairs or a single wall, pick Run and enter just its length.
Does the calculator handle inside and outside corners differently?
No. The 10% extra covers the miter cuts at all corners in an ordinary room. A room with many outside corners, such as a bay window, wastes more at the miters, so use a higher percentage there.
Does the height of the baseboard change how much I need?
No. The quantity is the length along the walls, in linear feet. A taller profile changes the price per foot and the lengths the store carries, but not the number of feet you need.
Worked example
A room is 14 ft by 11 ft with 2 doorways of 3 ft each. The walls add up to 2 × (14 + 11) = 50 ft, and taking off the doorways leaves 50 − 2 × 3 = 44 ft. With 10% extra, the amount to buy is 44 × 1.10 = 48.4 ft. By total length, that is 7 pieces of 8 ft, 5 pieces of 12 ft or 4 pieces of 16 ft. A count based on total length is a minimum: check that each wall can be cut from whole pieces with the seams where you want them.
Common mistakes
- Forgetting to subtract the doorways. Baseboard stops at the casing, so each opening shortens the run. Closet doors with their own casing count too.
- Buying exactly the wall length. A single mis-cut miter can consume an entire piece. Round up to whole pieces and keep the extra for repairs.