WheelbarrowMath

Flooring Calculator

Work out how many boxes of laminate, vinyl plank, or hardwood you need, plus underlayment.

Rooms to floor
  1. Area 1
    ft
    ft

For an odd shape, split it into rectangles, circles, and triangles; they're added together.

Layout
%

Mullican Flooring suggests 5% for straight layouts and 10–15% for diagonal or herringbone.

sq ft

It's printed on the box or product page.

sq ft

Check the roll. Some floors come with underlayment attached.

Prices (typical US prices; edit for your area)
/sq ft

Laminate typically runs $1–$6 a sq ft, vinyl plank $2–$10, and hardwood $4–$15.Laminate typically runs $11–$65 a m², vinyl plank $22–$110, and hardwood $43–$160.

Your Results

Calculating …

How Much Flooring Do I Need?

Square feet to buy = room area × 1.05 (straight layout) or × 1.10–1.15 (diagonal or herringbone)

Then divide by the square feet in a box and round up.

Worked example. A 15 × 12 ft room is 180 sq ft. With 5% extra that’s 189 sq ft. At 20 sq ft a box you need 10 boxes (200 sq ft), plus 2 rolls of 100 sq ft underlayment.

How Much Extra?

Mullican Flooring, a hardwood maker, recommends:

LayoutExtra
Straight5%
Diagonal or herringbone10–15%

Rooms with lots of corners, closets, and doorways create more offcuts, so lean high there. Buy all your boxes at once, ideally from the same production lot, so the color and texture match.

Underlayment

Floating floors (most laminate, many vinyl planks, and engineered wood) sit on an underlayment that cushions, quiets, and evens out small bumps. Some planks have it attached. Underlayment is sold in rolls; check the roll label for coverage and enter it in the calculator.

What It Costs

HomeGuide gives these ranges per square foot:

FloorMaterialsInstalled
Laminate$1–$6$4–$14
Vinyl plank (LVP)$2–$10$4–$16
Engineered hardwood$2–$9$7–$20
Solid hardwood$4–$15$11–$25

Underlayment adds about $0.50–$3.50 a sq ft installed.

Frequently Asked Questions

How Much Extra Flooring Should I Buy?

Mullican Flooring suggests about 5% for straight installations and 10–15% for diagonal or herringbone layouts, plus a box or two for future repairs.

How Do I Measure a Room for Flooring?

Measure length and width in feet and multiply. Include closets, and split L-shaped rooms into rectangles. Measure to the wall, not the baseboard.

Do I Need Underlayment?

Most floating laminate and vinyl floors and engineered wood need it, unless the planks have a pad attached. Check the flooring maker’s instructions.

How Much Does Flooring Cost?

HomeGuide puts laminate at $1–$6 a sq ft for materials ($4–$14 installed), vinyl plank at $2–$10 ($4–$16 installed), and solid hardwood at $4–$15 ($11–$25 installed).

Sources

Prices are national ballparks checked October 2026. Local prices vary.