How to Calculate Room Area and Square Footage
Area measurement is essential for flooring, tiling, painting, landscaping and real estate. The most common shape is a rectangle (multiply length by width). For irregular rooms, divide into rectangles and add the areas together.
Flooring and Tiling Calculations
Always add 10% to your calculated area for straight-lay flooring or paint coverage. Add 15% for diagonal floor patterns or irregular tiles due to additional cuts. For example, a 25 m² room requires 27.5 m² of straight-lay flooring or 28.75 m² for diagonal patterns. Order materials in whole packets and keep leftovers for future repairs.
Square Metres vs Square Feet
Property listings in the US use square feet; the UK, Australia and most of the world use square metres. 1 square metre = 10.764 square feet. A 100 m² apartment = 1,076 sq ft. A typical UK 3-bedroom house is 85–95 m² (915–1,022 sq ft). A US single-family home averages around 186 m² (2,000 sq ft).
Frequently Asked Questions
How do I calculate square footage of a room?
Measure the length and width of the room in feet, then multiply: area = length × width. For a 15 ft × 12 ft room: 15 × 12 = 180 sq ft. For L-shaped rooms, divide into rectangles, calculate each, then add. Always measure at the widest points.
How do I convert square metres to square feet?
Multiply square metres by 10.764. So 20 m² × 10.764 = 215.3 sq ft. To convert square feet to square metres, divide by 10.764 (or multiply by 0.0929).
How much flooring do I need?
Calculate your room's square footage, then add 10% for waste and cuts (15% for diagonal patterns or tiles). For example, a 200 sq ft room needs 220 sq ft of flooring ordered. Always order slightly more than calculated to account for offcuts and future repairs.
How do I calculate the area of a circle?
Area = π × r² where r is the radius (half the diameter). For a circular room or garden feature 10 metres in diameter: r = 5m, area = 3.14159 × 25 = 78.5 m². Our calculator handles circles, rectangles, triangles and more.
What is the difference between area and perimeter?
Area is the space inside a shape (measured in square units: m², ft², cm²). Perimeter is the total length of the boundary of a shape (measured in linear units: m, ft, cm). Both are useful for different purposes — area for flooring and paint, perimeter for fencing and skirting boards.