How to use this calculator
Measure the room at its widest points. For an L-shaped room, calculate each rectangular area separately. Find the square-foot coverage on the flooring carton and set an allowance suited to your cutting pattern.
The formula
A worked example
A 12 × 15 ft room is 180 sq ft. Adding 10% gives 198 sq ft. At 22 sq ft per carton, you need exactly 9 cartons.
Assumptions & limitations
Assumes one rectangular room. Waste is user-selected, not a universal installation recommendation. Pattern matching, damaged planks, closets, and future repair stock may change your order.
Common questions
Do I round the area up first?
No. The calculator preserves the full area and rounds up only the final number of cartons.
Can this estimate underlay?
The area is useful for underlay, but its roll coverage and overlap requirements should be calculated separately.
Units reference
The calculation follows the method above. This reference supports the units and conversions.
NIST: units and conversion factors ↗Formula and worked example checked against automated test cases. About our methodology.