Measure the room and read the square feet on one box of your flooring. You get the boxes of laminate, vinyl plank or wood to buy with the extra for cuts, the underlayment, the quarter round and the transition strips.
Flooring to buy
10 boxes185 sq ft with 10% extra for cuts · 177 sq ft of underlayment · 49 ft of quarter round · 1 transition strip
Quick answer: multiply the room’s length by its width, add 10% for cuts laid straight (15% diagonally, up to 20% in herringbone), and divide by the square feet on one box, rounding up. A 14′ × 12′ room needs 185 sq ft: 10 boxes of 20 sq ft, plus 177 sq ft of underlayment and 49 ft of quarter round.
How to use the flooring calculator
- Measure the room wall to wall, and read the square feet printed on one box of your laminate, vinyl plank or wood. Add a closet or hall that gets the same floor.
- Pick the layout, say whether the room has many corners, closets or cabinets, and how many doorways it has.
- Read the boxes to buy, the underlayment, the quarter round and the transition strips. Copy link keeps the result.
The rules the calculator uses
From LL Flooring’s guide to estimating a flooring project:
- Extra for cuts: 7–10% laid straight (the calculator buys 10%), 15% diagonally, 15–20% in herringbone or another complex pattern (it buys 20%), and 3–5% more for a room with many obstacles (it adds 5%).
- Underlayment: the floor’s area plus 5%. A moisture barrier, where one is needed, the area plus 10% for the overlaps.
- Quarter round or shoe molding: the room’s perimeter, less the doorways. Transition strips: one for each doorway where the new floor meets another.
- Round up to whole boxes, and keep one back for future repairs.
Boxes for common room sizes
Laid straight with 10% extra, one doorway:
| Room | Floor | Buy | Boxes of 20 sq ft | Boxes of 24 sq ft |
|---|---|---|---|---|
| 10′ × 10′ | 100 sq ft | 110 sq ft | 6 | 5 |
| 10′ × 12′ | 120 sq ft | 132 sq ft | 7 | 6 |
| 12′ × 12′ | 144 sq ft | 159 sq ft | 8 | 7 |
| 12′ × 14′ | 168 sq ft | 185 sq ft | 10 | 8 |
| 12′ × 16′ | 192 sq ft | 212 sq ft | 11 | 9 |
| 14′ × 16′ | 224 sq ft | 247 sq ft | 13 | 11 |
| 15′ × 20′ | 300 sq ft | 330 sq ft | 17 | 14 |
Three worked examples
A 14′ × 12′ bedroom, laid straight. 168 sq ft plus 10%: 185 sq ft, or 10 boxes of 20 sq ft. 177 sq ft of underlayment, and 49 ft of quarter round round the walls, less the one doorway.
A 15′ × 12′ living room in herringbone, with a fireplace and two doorways. 180 sq ft plus 20% for the pattern and 5% for the obstacles: 225 sq ft, or 10 boxes of 22.5 sq ft. 48 ft of quarter round and 2 transition strips.
A 20′ × 10′ room and a 40 sq ft hall. 240 sq ft plus 10%: 264 sq ft, or 15 boxes of 18.4 sq ft, and 252 sq ft of underlayment. Measure the hall’s walls for its quarter round.
Common flooring mistakes
- Buying boxes from different lots. Check the lot number on every box: the color can shift between runs. Buy it all at once.
- Skipping the acclimation. Laminate and wood move with the humidity; leave the boxes in the room as the maker’s instructions say before you lay them.
- Measuring round the furniture. Measure wall to wall; the floor goes under the bed and the sofa too.
- Forgetting the closets. A closet is a small room with a lot of cuts. Add it, and its walls to the quarter round.
Then furnish it: the rug size calculator for the rug on the new floor, the room square footage calculator for an L-shaped room, and the free 2D room planner to try the furniture.
Read next
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- Budget decorating ideas that read expensive
- Spring kitchen refresh ideas without a renovation
Flooring questions
How much flooring do I need?
The room’s length × width in square feet, plus 10% for cuts laid straight, 15% diagonally or up to 20% in herringbone. Divide by the square feet on one box and round up.
How many boxes of flooring do I need?
The square feet to buy (the floor plus the extra) divided by the square feet printed on one box, rounded up. A 12′ × 12′ room laid straight needs 159 sq ft: 8 boxes of 20 sq ft or 7 of 24 sq ft.
How much extra flooring should I buy?
7–10% laid straight, 15% diagonally and 15–20% in herringbone, plus 3–5% for a room with many corners or cabinets. Keep a box back for repairs.
How much underlayment do I need?
The floor’s area plus 5%. For a 14′ × 12′ room, about 177 sq ft.
How much quarter round do I need?
The room’s perimeter less the doorways. A 14′ × 12′ room has 52 ft of wall; with one 3 ft doorway, 49 ft.
Is this a laminate or a vinyl plank flooring calculator?
Both, and wood too: the box’s square feet is what differs, and the calculator asks for it.