Baseboard / Trim Calculator

Estimate baseboard, trim, and molding linear feet plus piece count based on room size and waste.

Baseboard / Trim Calculator
✓ Your estimate
Estimated trim needed
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linear ft incl. waste
Switch display unit only.
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Room perimeter
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Net linear ft
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Linear ft incl. waste
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Pieces
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What this estimate includes

This estimate shows room perimeter, net trim length after openings, adjusted linear feet, and pieces needed.

How it’s calculated

Perimeter = 2 × (length + width)
Net linear feet = perimeter − openings
Adjusted linear feet = net linear feet × waste %
Pieces = adjusted linear feet ÷ piece length, rounded up

Before you order

Miter cuts, coped corners, mistakes, and layout choices can add waste. Confirm piece lengths available at your store before buying.

Frequently Asked Questions

Should I subtract door openings?
Yes, subtract openings where baseboard or trim will not be installed.
How much waste should I add for trim?
Ten percent is a common planning allowance; complex rooms may need more.
Does this include casing or crown molding?
It can be used for any straight trim length, but enter the correct room or wall lengths for that trim type.
What piece length should I buy?
8 ft and 12 ft are the most common lengths at hardware stores. 12 ft pieces reduce the number of joints in a room, which means fewer seams to fill and sand.
How do I measure a room for baseboard?
Measure each wall length and add them together to get total perimeter. Then subtract the width of each door opening where baseboard will not be installed. Use that net figure as your linear footage.
What is the difference between baseboard and quarter round?
Baseboard covers the gap between the wall and the floor. Quarter round is a small molding added at the base of the baseboard to cover gaps between the baseboard and the flooring surface, common with floating floors.
Do I need to prime baseboard before painting?
Yes, unfinished wood baseboard needs primer before paint for proper adhesion and even coverage. Pre-primed baseboard skips this step. MDF baseboard especially needs sealed ends to prevent swelling.
Disclaimer: This calculator provides estimates only. Actual quantities depend on product coverage, jobsite conditions, waste, and supplier details. Verify all quantities before ordering. See all interior material calculators.