Flooring Calculator
Enter the room size and the coverage per box to see how many boxes of flooring to buy, plus underlayment and baseboard or quarter round for the edges.
Enter the size of the room.
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How to use the flooring calculator
- Measure the room wall to wall at floor level. Include closets you'll floor, and measure L-shaped rooms as separate rectangles (or add them with the square footage calculator and use I know the area).
- Enter the coverage per box from the product label — it varies widely between products.
- Set the extra. 10% covers cuts and the offcuts at row ends in a straight layout. Diagonal and herringbone layouts need 15% or more.
- Read the boxes to buy and the underlayment and trim for the edges.
How to calculate flooring
Worked example: a 14 × 12 ft living room with laminate at 20 sq ft per box
- Area: 168 sq ft; plus 10% = 184.8 sq ft
- Boxes: 184.8 ÷ 20 = 9.24 → 10 boxes (200 sq ft)
- Quarter round: perimeter 52 ft − 3 ft for one doorway = 49 ft → 7 pieces of 8 ft with 10% extra
How much extra flooring should you buy?
| Layout | Typical extra |
|---|---|
| Straight lay, simple rectangular room | 5–10% |
| Many corners, closets or small rooms | 10–15% |
| Diagonal layout | 15% |
| Herringbone or chevron | 15–20% |
Keep at least one unopened box after the job. Discontinued colors and different production lots make exact matches hard to find years later.
Before you install
- Acclimate the flooring in the room for as long as the manufacturer specifies — especially solid and engineered wood.
- Check the subfloor is flat, clean and dry. Most floating floors have a flatness tolerance in the installation guide.
- Underlayment: some vinyl planks and laminates have a pad attached; adding another layer can void the warranty. Set the underlayment field to 0 in that case.
- Expansion gap: floating floors need a gap at the walls, hidden by baseboard or quarter round.
Frequently asked questions
How many boxes of flooring for 500 square feet?
With 10% extra you need 550 sq ft: 28 boxes at 20 sq ft per box, or 23 boxes at 24 sq ft per box.
Do I include closets and the area under appliances?
Include closets. Under fixed cabinets and islands, no. Under a fridge or range, most people run the floor underneath so the appliance can be moved out.
How do I measure a room with a bay window or angled wall?
Split it into a rectangle plus a trapezoid or triangle and add them up with the square footage calculator.
Is flooring sold by the square foot or by the box?
Priced by the square foot but sold in whole boxes, so the cost is based on the boxes you actually buy.