Area Calculator
Area of the shapes real projects come in — rectangle, circle, triangle, trapezoid and L-shape — answered in square feet, square meters and square yards at once.
Area is a shape before it is a number
Every material estimate on this site starts from an area — and real spaces are rarely one clean rectangle. This calculator holds the five shapes projects actually come in: the rectangle, the circle, the triangle, the trapezoid, and the L-shape, which it treats the way estimators do, as two rectangles added together. Pick the shape, measure it, and the area comes back in square feet, square meters and square yards together, because different materials are sold against different units.
Rectangle = length × width · Circle = π × radius² · Triangle = base × height ÷ 2 · Trapezoid = (a + b) ÷ 2 × distance · L-shape = rectangle 1 + rectangle 2
Example: a 12 × 15 ft room is 180 sq ft — 16.72 sq meters, 20 sq yd. A round patio of radius 10 ft is 314.16 sq ft. A trapezoid bed 12 ft on the long side, 8 ft on the short side and 10 ft across is 100 sq ft.
Splitting the odd shapes
Any floor plan that is not on the list decomposes into shapes that are: an L or T or U is rectangles; a bay window's floor is a trapezoid or a triangle on a rectangle; a curved bed's edge can be squared off into a rectangle plus a half-circle, close enough for ordering. Sketch it, split it, measure each piece in the same units, and add — the total is honest even when the outline is not.
Measure to the outside of the space the material must cover, and keep every measurement in one unit before you start: mixing a width in inches into a length in feet is the quiet error behind most wrong orders. Waste does not belong in the area itself — each material calculator adds its own allowance openly, for its own reasons.
Frequently asked questions
How do I measure an L-shaped room?
Split it into two rectangles at the inside corner, measure each one, and add the two areas. The L-shape option above does exactly that — enter the two rectangles you would have measured separately. Any split line works, as long as the two rectangles cover the floor once each and never overlap.
What is the area of a circle if I only know the diameter?
Halve it — the radius is half the diameter — and enter the radius. A 20 ft round patio has a radius of 10 ft and an area of about 314 sq ft. Squaring the diameter by mistake gives an answer four times too big, the classic circle error.
Which unit should I order in?
Whatever the material is sold in: carpet and some flooring in square yards, tile and most materials against square feet, metric suppliers in square meters. The result states all three so the number you carry to the store matches the label on the shelf.
Why is there no waste allowance here?
Because area is a measurement, not an order. Waste belongs to the material — tile cuts waste differently from mulch settling — so each material calculator adds its own allowance openly on its own result. Converting an area with waste baked in would corrupt every estimate downstream.
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