A worked example: 12ft × 10ft bedroom
A bedroom measuring 12ft by 10ft has a square footage of exactly 120 sq ft (12 × 10), which converts to 11.15 m² — the figure a metric-only supplier or contractor would need for the same room.
The formula: length times width, in feet
Area (sq ft) = length (ft) × width (ft). The square-meter equivalent then comes from multiplying that square-footage figure by 0.09290304, the exact conversion factor for one square foot in square meters. For the 12ft × 10ft bedroom, that's 120 × 0.09290304 = 11.1484 m², shown rounded to 11.15 m².
A bigger space: 25ft × 18ft living room
A 25ft by 18ft living room comes out to 450 sq ft (25 × 18), equivalent to 41.81 m². The same single multiplication scales to any rectangular room, from a small bedroom up to a 40ft × 30ft shop floor, which works out to 1,200 sq ft — 111.48 m².
Why square footage stays in feet even on metric sites
"Square footage" is a specific, commonly searched real-estate term that conventionally means the area in square feet, even in countries where every other measurement on a property listing is metric. Giving both the sq ft figure and its square-meter equivalent side by side avoids forcing a reader to convert by hand, and it's also exactly the starting figure needed by materials calculators — like a plaster calculator — that expect a wall or floor area rather than a raw length and width.