Flooring Calculator

How to use the calculator

1. Units: keep Imperial for feet, or switch to Metric if your plans are in meters.
2. Room length and width: measure wall to wall at floor level, at the longest points. For an L-shaped room, split it into two rectangles and run the calculator for each.
3. Waste allowance: 10% for a standard straight layout, 15% for diagonal or herringbone patterns and rooms with many corners.
4. Coverage per box: the square feet per carton printed on the box or product page, for example 20 or 23.4 sq ft.
5. Price per sq ft (optional): flooring is usually priced per square foot, not per box. Leave it at 0 to skip the cost line.

How the calculation works

The calculator multiplies length by width, adds the waste allowance and divides by the coverage of one box. You can't buy part of a box, so the result is always rounded up:

Boxes = Length × Width × (1 + Waste ÷ 100) ÷ Coverage per box, rounded up to a whole box.

• Area you'll buy = boxes × coverage per box. It is always at least the area including waste.
• Cost = area you'll buy × price per sq ft, because you pay for full boxes.
• Perimeter = 2 × (length + width). Use it to estimate baseboard or quarter round, but subtract the width of each doorway and any run along cabinets.

The calculator assumes a rectangular room. It doesn't add underlayment, transition strips, stair nosing or sales tax.

Examples

1. Living room, 14 × 12 ft, laminate

The room is 168 sq ft. With 10% waste you need 184.8 sq ft. Boxes hold 20 sq ft, so you buy 10 boxes (200 sq ft). At $3.49 per sq ft the flooring costs $698.00. The perimeter is 52 ft; a 3-ft doorway brings the baseboard run down to 49 ft.

2. Kitchen laid on the diagonal, 16 × 9.5 ft, vinyl plank

152 sq ft plus 15% waste is 174.8 sq ft. With 23.4 sq ft per box you need 8 boxes (187.2 sq ft), or $522.29 at $2.79 per sq ft.

3. How the waste allowance changes the order

Same 14 × 12 ft room. Because boxes round up, moving from 10% to 15% waste costs nothing extra here, while cutting it to 5% leaves almost no margin.

Before you install

• Acclimate the planks. Pergo's installation guide asks for unopened cartons to lie flat in the room for 48 to 96 hours, at least 96 in very dry or very humid climates. Vinyl and engineered wood have their own rules, so follow the instructions in your box.
• Leave an expansion gap. Floating floors move with temperature and humidity. Laminate guides typically call for 1/4 to 3/8 in at every wall and fixed object, more in very long rooms, hidden later by baseboard or quarter round.
• Undercut door jambs so the planks slide underneath instead of being scribed around the casing.
• Keep a few spare planks for future repairs; a later production run may not match.