Planimeters are excellent area measuring tools to use when you measure irregular shaped areas on plans or drawings. If you want to trace around an irregular shape, like a swimming pool, golf course green, storm water management ponds, an organ or tumor on an x-ray, planimeters are the tool of choice. You simply set your scales up, then trace around the objects perimeter, and close the loop. The planimeter will tell you the square units of area within the loop.
Many people try to avoid using a planimeter by making rectangles and triangles in their irregular shape. This only estimates the area and it is a time consuming process. But with a planimeter, you get accurate results, and done quickly. You'll be surprised at exactly how accurate a planimeter is. They are considered an excellent area measuring device.
