Baseboard Calculator
Calculate baseboard and shadow gap trim by room size or known perimeter. The tool deducts doorway widths, adds cutting waste and shows how many pieces you should buy.
Baseboard Calculator
Calculate linear meters, number of baseboard pieces and cost with doorway deductions.
Next step after baseboard
If the perimeter is done, the next useful move is usually the floor finish or the final room budget.
When this estimate is most useful
- For standard rooms. Use length and width and let the calculator build the perimeter.
- For complex layouts. If you already measured perimeter manually, switch to custom mode.
- For purchasing. The result gives you total length, piece count and a quick cost estimate.
Common calculation mistakes
Using the full perimeter without doorway deductions. In most rooms the baseboard does not pass through the doorway, so leaving those openings in the number usually overstates the order.
Ignoring cuts and corners. Small walls, awkward corners and outside returns create more waste than the clean perimeter figure suggests.
Thinking only in linear feet. You buy fixed-length pieces, not loose footage. The piece count matters just as much as the total perimeter.
What to check before buying
Verify the length of one piece. Baseboards that look similar can come in very different lengths, and that changes the final quantity right away.
Decide on corners and connectors early. Even if you plan to miter everything, it is worth deciding up front whether you need matching trim accessories.
Watch the finish and batch. Painted and laminated profiles can still vary slightly. Buying the full run in one go is safer, especially for long visible walls.
FAQs
Can this calculator be used for shadow gap baseboards (concealed skirting)?
Yes. For shadow gap baseboards and drywall reveal trim profiles, calculate the perimeter of all finished walls and subtract doorway openings. Because aluminum shadow profiles and drywall trims require precise miter joints at inside and outside corners, we recommend selecting an 8–10% cutting allowance.
How much baseboard do I need for a 1,500 sq ft house?
A typical 1,500 sq ft house has multiple rooms and hallways with an average interior perimeter between 350 and 420 linear feet (105–130 m). After subtracting approximately 8 to 12 interior door openings (each 30–36 inches or 0.8–0.9 m) and adding 8% for corner cuts, you will generally need 340–380 linear feet (about 43 to 48 eight-foot trim pieces).
Should I deduct door openings?
Yes. In most rooms, baseboard does not run through the door opening, so that width should be deducted from the perimeter.
How much waste should I allow?
Five to seven percent is often enough for a simple room. If there are more cuts, tricky corners or material defects, use a slightly higher reserve.