About this calculator
Laminate, luxury vinyl plank (LVP), engineered wood and solid hardwood are sold by the box, with each box covering a fixed number of square feet. This calculator measures your room, adds a waste allowance for cuts and end pieces, and rounds up to whole boxes so you know exactly what to order and what it will cost.
How to use it
- Measure the room’s length and width at the widest points, including closets and doorway areas you’ll floor.
- Set the waste allowance: 10% for a straight layout, 15% for diagonal, herringbone or rooms with many corners.
- Enter the coverage per box from the product label (commonly 18–30 sq ft).
- Enter the price per square foot to see the cost of the full boxes.
The formula
Area = length × width
Area with waste = area × (1 + extra%)
Boxes = area with waste ÷ coverage per box, rounded up
The cost is based on the full boxes you’ll actually buy, which is always a little more than the area of the room.
Worked example
These are the calculator’s starting values and the results they produce:
| Room length | 14 ft |
|---|---|
| Room width | 12 ft |
| Extra for cuts and waste | 10 % |
| Coverage per box | 20 sq ft |
| Price per sq ft | $3.00 |
Tips before you buy
- Keep one unopened box after the job for future repairs — discontinued flooring can be impossible to match.
- Let laminate and wood flooring acclimate in the room for 48–72 hours before installation (follow the manufacturer’s instructions).
- Most floating floors need a ¼–⅜ in expansion gap at the walls, hidden by baseboard or quarter-round.
- For L-shaped rooms, measure as two rectangles and add the areas.
Frequently asked questions
How much extra flooring should I buy?
Buy 10% extra for a standard straight installation and 15% or more for diagonal patterns, herringbone or rooms with lots of angles and doorways.
How many boxes of flooring do I need for a 12×14 room?
A 12 × 14 ft room is 168 sq ft. With 10% waste that is 184.8 sq ft, so with 20 sq ft boxes you need 10 boxes.
How do I measure a room for flooring?
Measure the length and width in feet and multiply. For irregular rooms, split the floor into rectangles, calculate each and add them. Include closets and the area under doors.
Should I buy extra flooring for future repairs?
Yes. Keeping one spare box lets you replace damaged planks later with an exact match. Flooring lines are discontinued often, and even the same product can vary in color between production runs.