Flooring and Square Footage Calculator

How to use the square footage calculator

1. Choose Metric (m, cm, m²) or Imperial (ft, in, sq ft).
2. The first section is a rectangular room. For each section, pick a Shape and enter its two dimensions in metres + centimetres or feet + inches (12 ft 6 in, or just 12.5 in the first box): - Rectangle (add): length × width; - Triangle (add): base × perpendicular height ÷ 2, for angled walls and bay corners; - Rectangle cut-out (subtract): an area that won’t be covered, such as a kitchen island, fixed cabinets or a hearth.
3. Click Add a section for each extra room or piece of an irregular room, and × to remove one. The area of each section is shown on its row.
4. Under Material, set the Waste allowance (%), the Coverage per box (optional) printed on the flooring box, and, if you like, the Price per unit of area (optional).
5. Read the Floor area, the same area In the other unit (square feet ↔ square metres), the Area with waste, the Boxes to buy and the Estimated cost. The steps below the results show every term of the sum.

Your measurements stay in your browser.

How square footage is calculated

Floor area is the sum of simple shapes:

Area = Σ rectangles (L × W) + Σ triangles (b × h ÷ 2) − Σ cut-outs

For an L-shaped living room, split the L into two rectangles along any wall line. For example, 5 × 4 m plus 3 × 2.5 m gives 20 + 7.5 = 27.5 m². With 10% waste you need 30.25 m² of material; with boxes of 2.2 m², 30.25 ÷ 2.2 = 13.75, so 14 boxes (30.8 m²). In imperial units, a 16 × 13 ft bedroom is 208 sq ft; with 10% waste that is 228.8 sq ft, or 10 boxes of 23.5 sq ft.

One square metre is about 10.764 square feet (1 ft = 0.3048 m by definition, so 1 sq ft = 0.09290304 m² exactly). The tool uses these exact factors, so switching units never changes the answer.

Measuring tips

• Measure wall to wall at floor level, at the longest and widest points, and round up to the next centimetre or half inch. Walls are rarely square.
• Include closets and the space under appliances that will sit on the new floor, and the area under door openings up to the threshold.
• Leave out fixed cabinets and islands only if the flooring will not run under them. Floating floors (laminate, click vinyl) must not be pinned under heavy fixed cabinets.
• Measure each room separately when the flooring changes direction or when a transition strip will separate them.

Waste allowance and buying tips

• 5–10% is typical for laminate, engineered wood or vinyl plank laid straight in regular rooms; 10–15% for diagonal or herringbone layouts, many small rooms, or lots of doorways and corners. Tile has its own calculator with grout joints.
• Buy all boxes from the same production lot so the colour matches, and keep one spare box for repairs.
• Leave boxes in the room for the acclimatisation time recommended by the manufacturer (often 24–48 hours) before installing.
• Don’t forget underlayment, vapour barrier, transition strips and baseboards: they are bought separately, by area or by length.
• The manufacturer’s installation instructions (expansion gaps, subfloor flatness, moisture limits) and local building codes prevail over any estimate.