Square Footage Calculator
Calculate area in square feet, square meters, and acres for any room or lot.
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Popular conversions
All unit conversions →Quick Tip
Pick the shape that matches the space: rectangle, circle or triangle.
About This Tool
Why use Square Footage Calculator?
Work out the area of a rectangle, circle or triangle in feet, metres or yards, and get the result in square feet, square metres, square yards and acres at once. Rectangles are length × width, circles are πr², and triangles are ½ × base × height.
A room 12 ft by 14 ft is 168 sq ft, which is 15.6 m² or 18.7 sq yd. For flooring, work room by room and add the totals rather than measuring the whole floor plan at once, and add 5–10% for cuts and waste before ordering material.
Key Benefits
Four area units at once
Square feet, square metres, square yards and acres, so quotes in any unit can be compared directly.
Three shapes covered
Rectangles for rooms, circles for patios and tanks, triangles for gables and awkward corners.
Exact conversions
1 m² is exactly 10.7639 sq ft and an acre is 43,560 sq ft, so the figures are precise rather than rounded rules of thumb.
How to use Square Footage Calculator
- 1
Pick the shape that matches the space: rectangle, circle or triangle.
- 2
Choose your measuring unit — feet, metres or yards.
- 3
Enter the dimensions; for a circle enter the radius, which is half the width across.
- 4
Read the area in all four units, then add a waste allowance before ordering.
Best use cases
Measure a room before ordering flooring or carpet.
Work out lawn or patio area for turf, gravel or paving.
Convert a property listing between square feet and square metres.
Express a plot size in acres.
Square Footage Calculator FAQs
How do I calculate square footage?
Multiply length by width in feet. A 10 ft by 12 ft room is 120 sq ft. For an L-shaped space, split it into rectangles and add the areas.
How many square feet are in a square metre?
10.7639 sq ft. To go the other way, divide square feet by 10.7639.
How much extra material should I order?
Usually 5–10% over the measured area for straight layouts, and up to 15% for diagonal patterns or rooms with many cuts.
How large is an acre?
43,560 square feet, or about 4,047 square metres — roughly the size of a football pitch without the end zones.
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