Flooring calculator: how much flooring do I need?
Measure the room, pick the flooring type, and enter the square feet printed on the box. You get the square feet to buy with waste added, the number of boxes, and underlayment rolls if you need them.
- Laminate, vinyl or wood
- Boxes from the label
- Underlayment
Vinyl plank isn't listed separately in the waste guide we use. Start with the laminate figure and check your product's install guide. Skip underlayment if your planks have a pad attached. Doing a whole room? The room materials calculator gives paint, flooring, baseboard and drywall from one set of measurements.
Before you lay flooring
How it works
Area = length × width. For an L-shaped room, split it into rectangles and add each one.
Waste follows LL Flooring's guide: 5% for laminate, 8% for hardwood, 10% for exotic hardwood, and an extra 15% for a diagonal or custom layout.
Boxes = area × (1 + waste) ÷ square feet per box, rounded up. The box size defaults to 20 square feet; change it to what your box says.
Underlayment = area ÷ roll size, rounded up. The default is a 100-square-foot roll, a common size such as MP Global's QuietWalk.
About this tool
Who it's for
For anyone putting down click-lock laminate, vinyl plank or hardwood in a room.
Example
You enterA 12x12 room, laminate, 20 sq ft per box
You get8 boxes and 2 rolls of underlayment.
What's different
- Uses a waste figure for your flooring type.
- Rounds to whole boxes from your box size.
- Adds underlayment rolls.
Gotchas and tips
- Closets and hallways add cuts, so count them.
- Buy enough from one lot so the color matches.
- Keep a box for repairs later.
Privacy: Runs entirely in your browser. Nothing you type is sent to us, and anything it remembers is saved on this device only.
Built and maintained by the GrabTheHammer team, using published figures from manufacturers and agencies, listed below. Updated November 2026. Spot a problem? Tell us.
Flooring questions
How much extra flooring should I buy?
LL Flooring suggests 5% for laminate and 8% for most hardwood. Add another 15% if you lay it on a diagonal or in a pattern.
How many boxes of flooring for a 12x12 room?
A 12x12 room is 144 square feet. With 5% waste that is about 151 square feet, so 8 boxes at 20 square feet each. Check your box, since sizes vary.
Do I need underlayment?
Most floating laminate needs it. Many vinyl planks have a pad attached and don't. Your flooring's install guide says which one you have.
Sources: LL Flooring: how to measure and waste by type; MP Global: QuietWalk roll sizes.