Calculate square feet from dimensions and combine up to 10 added or subtracted areas. Each region can be a rectangle, circle or triangle and can use its own measurement unit. Results include square metres, square yards, square inches and acres, with an area-by-area formula breakdown.
Use it to estimate the flat area of rooms, floors, walls and other measured surfaces. Split an L-shaped footprint into non-overlapping shapes. For a rectangular wall, use its length and height as the two dimensions and subtract windows or doors separately. Curved surfaces, arbitrary boundaries and sloped-roof projection are not modeled.
Use ordinary decimals with a decimal point or comma and no thousands separators. For example, 1,200 is interpreted as 1.2, not twelve hundred. Fractions, scientific notation and text with unit suffixes are not accepted; enter half an inch as 0.5.
Adding a region creates blank dimensions to complete before calculation. Editing, removing, or changing a shape or unit clears the old result. Reset restores one empty rectangle in Add mode using feet and inches. Inputs remain in component state and are not saved to URLs or browser storage.
Normalize dimensions to feet:
For a rectangle, multiply length in feet by width in feet. A 12 ft by 10 ft room has 120 square feet. Circles use diameter; triangles use base and perpendicular height.
No. Six inches is half a foot, so 12 feet 6 inches equals 12.5 feet. Use the separate feet and inches fields to avoid decimal-foot mistakes.
Add non-overlapping rectangles, or calculate an outer rectangle and subtract the missing section. Use one approach consistently to avoid counting overlaps or subtracting twice.
Valid dimensions are converted to preserve physical size, subject to floating-point rounding. Invalid or blank dimensions are cleared and their inches fields reset to zero. Complete them before calculating again.
No. It is geometric net area without material allowance, purchase rounding or jurisdiction-specific building and appraisal measurement rules.
計算房間、地面及多個區域的平方英尺面積。