How the Laminate Flooring Calculator Works
Enter your room's length and width in feet, pick your plank size and a waste factor, and the calculator returns the total square footage to order and how many boxes that is. It multiplies length by width for floor area, adds your waste percentage for cutting and repairs, then divides by the coverage of a box and rounds up to the next whole box. Add an optional price per square foot and it also estimates the material cost. Every number is computed in your browser as you type.
A Worked Example
Say you're flooring a 12 by 15 ft bedroom. The floor area is 12 times 15, or 180 sq ft. Add 10% waste for a straight layout and you need 180 times 1.10, or 198 sq ft. At the common 20 sq ft per box, that's 198 divided by 20, or 9.9 boxes, which rounds up to 10 boxes. Ten boxes give you 200 sq ft — just enough, with two square feet left as spares. At $2.50 per sq ft the laminate runs about $495 before underlayment and trim.
Waste, Boxes, and the Details That Trip People Up
The two things that change your order most are the waste factor and the coverage of the box you actually buy. A diagonal or herringbone layout wastes more at every angled cut, so it wants 15% instead of 10%. Box coverage isn't always 20 sq ft — wide and long planks often cover 22 to 24 — so divide by the number on the label, not a habit. Buy full boxes from a single dye lot, keep two or three planks as spares, and remember laminate can't be refinished the way hardwood can.
Laminate Flooring Calculator
Laminate Flooring Coverage Reference
Boxes needed by room size with 10% waste factor.
| Room Size | Area (sq ft) | With 10% Waste | Boxes (20 sq ft) |
|---|---|---|---|
| 8' × 10' | 80 | 88 | 5 |
| 10' × 12' | 120 | 132 | 7 |
| 12' × 12' | 144 | 158 | 8 |
| 12' × 14' | 168 | 185 | 10 |
| 14' × 16' | 224 | 246 | 13 |
| 15' × 20' | 300 | 330 | 17 |
| 20' × 20' | 400 | 440 | 22 |
How to Use This Calculator
- Measure and Enter Room Length: Measure the room's longest dimension in feet, including any closet or alcove the floor runs into, and enter it as the room length.
- Add Width, Plank Size, and Waste: Enter the room width, choose your plank size, and set the waste factor: 10% for a straight layout, 15% for diagonal or patterned installs. Add a price per sq ft if you want a cost estimate.
- Click Calculate: Hit Calculate to get your padded square footage and box count. The box count is already rounded up to whole boxes.
- Check the Breakdown and Order: Compare the boxes-needed figure against the coverage printed on the box you plan to buy, then order that many boxes plus underlayment and trim.
How It Works
Laminate is sold by the box, and every box covers a fixed number of square feet — often around 20. You find your room area in square feet, pad it with a waste percentage for cuts and mistakes, then divide by the coverage printed on the box to get how many boxes to buy. Because you can only buy whole boxes, the result always rounds up.
The basic rule:
- Measure length and width at the longest and widest points, and include closets and doorway thresholds if the floor runs into them
- Add 10% waste for a straight, plank-parallel-to-the-wall layout, and 15% for diagonal or herringbone patterns where angled cuts waste more material
- Stagger the end seams at least 8 to 12 inches from one row to the next so the floor locks tight and doesn't look like a repeating grid
A typical box holds 8 to 10 planks and covers 18 to 24 sq ft, so always divide your padded area by the exact coverage on the label rather than a guess. Unlike hardwood, laminate can't be sanded and refinished, so set aside two or three leftover planks stored flat for future repairs when a dye lot is discontinued. Let the boxes sit unopened in the room for 48 hours first so the planks reach the room's temperature and humidity before they're clicked together.
Tips & Considerations
- Confirm the coverage printed on your box before trusting a box count — wide or long planks often cover 22 to 24 sq ft, not the default 20.
- For rooms that aren't simple rectangles, split the floor into rectangles, calculate each, and add the square footage together.
- Order all your boxes at once from the same dye lot so the color and pattern match across the whole floor.
- Keep two or three leftover planks stored flat as spares — laminate can't be refinished and dye lots get discontinued.
- Buy underlayment and quarter-round trim in the same trip; the calculator covers the planks, not the pad or the edge molding.
Frequently Asked Questions
How much waste should I add to my laminate order?
Add 10% for a standard straight layout with planks running parallel to the longest wall. Bump it to 15% for diagonal, herringbone, or chevron patterns, and for rooms with lots of jogs, closets, and doorways that force extra cuts. A very experienced installer working a simple rectangle can get away with 8%. The waste covers the cut-off ends of each row, damaged planks, and a small stash for repairs.
How many boxes of laminate do I need for a 12×15 room?
A 12 by 15 ft room is 180 sq ft. Add 10% waste and you need 198 sq ft. At 20 sq ft per box that's 9.9 boxes, which rounds up to 10 boxes. If the box you're buying covers 22 sq ft instead, 198 ÷ 22 is exactly 9 boxes. Always divide by the coverage printed on your specific box, then round up to the next whole box.
Do I need underlayment under laminate flooring?
Yes, laminate needs a thin foam or felt underlayment for cushioning, sound damping, and a moisture barrier over concrete. Many planks come with the pad already attached — check the box, because you should never stack a second underlayment under a plank that already has one. If it's bare, buy a roll separately; rolls run 100 to 200 sq ft and cost roughly $20 to $50, and over a concrete slab you'll also want a 6-mil vapor barrier.
How big should the expansion gap be around the edges?
Leave a gap of about 1/4 to 3/8 inch between the flooring and every wall, cabinet, and vertical surface so the floor can expand and contract with temperature and humidity. Spacers set against the wall during installation keep the gap even, and baseboard or quarter-round trim covers it afterward. Skipping the gap is the most common cause of a laminate floor buckling or peaking at the seams.
How much does it cost to floor a room with laminate?
Materials run about $1 to $2 per sq ft for budget laminate, $2 to $4 for mid-range, and $4 to $6 for premium waterproof lines. For a 180 sq ft room padded to 198 sq ft at $2.50 per sq ft, the laminate alone is about $495 before underlayment and trim. DIY installation is the norm and free; hiring a pro adds roughly $2 to $4 per sq ft in labor.
Can I install laminate in a bathroom or basement?
Standard laminate swells when it gets wet, so keep it out of full bathrooms and any area with standing-water risk. Waterproof laminate with a sealed rigid core is rated for bathrooms and below-grade basements, but you still need a vapor barrier over concrete. For a kitchen or half-bath, waterproof laminate is fine; for a floor that gets soaked, vinyl plank is the safer pick.
How long does laminate flooring last?
Good laminate lasts 15 to 25 years in a home. Check the abrasion rating: AC3 handles normal residential traffic, and AC4 or AC5 stands up to heavy or light commercial use. Because it can't be refinished, its lifespan comes down to the wear layer, so use furniture pads, wipe up spills quickly, and skip steam mops and abrasive cleaners.