By M.L. Browne
Updated Aug 30, 2022
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Determining the square area of a rectangular space is straightforward: multiply its length by its width. When dealing with polygons that have more than four sides or irregular shapes, you must break the area into a combination of standard geometric shapes and apply the appropriate formulas to each segment.
Identify whether the area can be partitioned into squares, rectangles, triangles, rhombuses, trapezoids, parallelograms or other regular polygons. If the space is irregular, subdivide it into smaller, well‑defined shapes that can be measured accurately.
Adopt the smallest common unit that still provides manageable numbers—for example, use centimeters instead of meters, or meters instead of kilometers. A finer scale reduces rounding error and increases the reliability of your final calculation.
Using a calibrated metric measuring tool, record the dimensions of every regular shape. Apply the standard geometric formula for each type (area = length × width for rectangles, area = ½ × base × height for triangles, etc.). Sum the individual results to obtain the total area in the chosen unit.
If your measurements are in centimeters, divide the aggregate area by 10,000 to convert to square meters. If you used kilometers, multiply the result by 1,000,000. The conversion factor depends on the unit of the intermediate calculations.
