Flooring Calculator
Calculate flooring for any room — room size, waste allowance, and box coverage turn into total square feet and boxes to buy.
Whether you are laying laminate, vinyl plank, or hardwood, this free flooring calculator tells you how much to buy. Enter your room size, pick a waste allowance (10% is standard), and enter the square footage printed on the box — you get the total with waste and the number of whole boxes to purchase.
10% standard; 15% for diagonal or patterned lays.
Printed on the box (common: 15-25 sq ft).
How to use this calculator
- Step 1: Measure your room length and width in feet (add closets and alcoves to the total).
- Step 2: Set the waste allowance — 10% for straight lays, 15% for diagonal or patterned installs.
- Step 3: Enter the square footage per box from your flooring product packaging.
- Step 4: Click Calculate to see your room area, area with waste included, and whole boxes to buy.
The formula
Total sq ft = length x width x (1 + waste%). Boxes = round up(total sq ft / sq ft per box).
Worked example
A 12x15 ft room is 180 sq ft. With 10% waste that is 198 sq ft, and at 20 sq ft per box you buy 10 boxes (covering 200 sq ft). With no waste allowance the same room needs exactly 9 boxes.
Frequently Asked Questions
How much extra flooring should I buy for waste?
Buy 10% extra for a standard straight installation — cuts at walls, doorways, and board ends always waste some material. Go to 15% for diagonal layouts, herringbone patterns, or rooms with lots of angles and closets. Keep one full spare box after the job for future repairs; dye lots change and matching later is hard.
What does square feet per box mean?
Flooring is sold in boxes that cover a fixed area, printed on the box or product page — commonly 15 to 25 sq ft for laminate and vinyl plank. You cannot buy a partial box, so the calculator rounds up to whole boxes. Enter the exact number from your product so the box count is right.
Should I measure closets and odd-shaped rooms separately?
Yes. Measure closets, hallways, and alcoves and add their area in — they eat flooring just like the main room. For L-shaped or irregular rooms, split them into rectangles, calculate each, and add the areas together. This calculator takes the total length and width, so add the rectangles up first.
Do I need to acclimate flooring before installing?
Yes for laminate, hardwood, and most vinyl plank. Stack the unopened boxes in the room for 48-72 hours so the material adjusts to your home temperature and humidity. Skipping acclimation is a common cause of gaps and buckling, and many manufacturer warranties require it.