Flooring details
Type feet and inches like 12'6" or just 12.5. Add a room for each space, or tick Subtract for a kitchen island. Everything is saved on this device.
About the flooring calculator
This free flooring calculator tells you how many boxes of flooring to buy. It is made for laminate, vinyl plank, engineered wood and other flooring sold by the box. Enter your rooms, pick the box size and the pattern, and it adds the right waste and rounds up to whole boxes.
It also shows the leftover, the underlayment you need and the number of transition strips. Add a price to see the cost.
Features
- Boxes, rounded up — never short by half a box
- Box size presets — 20, 22 and 24 sq ft (1.8, 2.0 and 2.2 m² in metric), or type your own
- Waste by pattern — straight 5%, diagonal 10%, herringbone 15%, or your own percent
- Any room shape — rectangles, triangles, circles and trapezoids, with a Subtract box for an island
- Leftover — see what stays in the boxes
- Underlayment and strips — underlayment area and one transition strip for each doorway
- Planks and cost — optional plank size gives the plank count; price by the box or by the square foot
- Saved on this device — the list is still there in the shop
How to use it
- Choose Feet & inches or Metres & cm
- Enter the length and width of the first room. Use Add another room for more
- Tick Subtract on an area to take it off, like a kitchen island
- Pick the pattern, then the box size from the box label
- Enter the number of doorways, and a price if you want the cost
- Read the boxes and press Copy the list
How much waste should I add?
Cutting along walls, doors and corners wastes flooring. The more complex the layout, the more you lose:
| Pattern | Extra to add | Why |
|---|---|---|
| Straight | 5% | Few cuts, ends reused |
| Diagonal | 10% | Every end is cut at an angle |
| Herringbone | 15% | Many small cuts and a matching pattern |
Use more for a room with many corners, a hallway or stairs. Pick My own % to type another number.
Worked examples
These numbers come from the calculator:
| Room | Waste | Box | Result |
|---|---|---|---|
| 12 × 10 ft, straight | 5% (126 sq ft) | 20 sq ft | 7 boxes, 14 sq ft left over |
| 15 × 10 ft, straight | 5% (157.5 sq ft) | 20 sq ft | 8 boxes, 2.5 sq ft left over |
| 15 × 10 ft, diagonal | 10% (165 sq ft) | 20 sq ft | 9 boxes, 15 sq ft left over |
| 15 × 12 ft minus a 3 × 4 ft island, diagonal | 10% (184.8 sq ft) | 22 sq ft | 9 boxes, 13.2 sq ft left over |
| 4 × 3.5 m, herringbone | 15% (16.1 m²) | 2.2 m² | 8 boxes, 1.5 m² left over |
The 15 × 12 ft room: 15 × 12 = 180, minus 12 for the island is 168 sq ft. With 10% that is 184.8 sq ft. Divide by 22, which is 8.4, so you buy 9 boxes. At $45 a box the cost is $405.
Underlayment and transition strips
Most laminate and many vinyl floors need an underlayment. The calculator shows the floor area, rounded up, with no extra, because underlayment is laid edge to edge. Check the roll size on the package. Many rolls cover 100 sq ft.
A transition strip covers the gap where the floor meets another floor in a doorway. Enter the number of doorways and you get one strip each. Strips are sold in lengths of about 6 ft, so check the width of your doors.
Frequently asked questions
How many boxes of flooring do I need?
Multiply length by width for the area, add 5–15% for waste, and divide by the area in one box. Round up. A 12 × 10 ft room with 5% waste is 126 sq ft, which needs 7 boxes of 20 sq ft.
How much extra flooring should I buy?
Plan on 5% for a straight layout and 10–15% for diagonal or herringbone. It is smart to keep a few spare planks for a later repair.
Does the calculator work for vinyl plank and laminate?
Yes. Any flooring that comes in boxes with a square foot or square metre figure on the label works the same way.
What is the difference from the tile calculator?
The tile calculator counts tiles and grout lines. This one is for boxes, and adds underlayment, leftover and transition strips.
Do I pay for the leftover?
Yes. You buy whole boxes, so the leftover is paid for. The cost by area line shows the price of the whole boxes.
Should I buy all boxes at once?
Yes, from the same batch number. Colour can change a little between batches.
Good to know
- Measure the room at its widest points, and add closets.
- Floor under cabinets does not need flooring, so only measure what you can see.
- Let planks rest in the room for a day or two before you install.
- All numbers are estimates. Check the package for the exact coverage.
- Everything stays on your device.
Related tools
- Tile & Flooring Calculator — tiles, grout and boxes
- Square Footage Calculator — the area of odd rooms
- Paint Calculator — paint for the walls
- Drywall Calculator — sheets for new walls
- Unit Converter — square feet and square metres
