Measure the length and width of your backyard or any other area, the area which you want to know in acres. This requires the corners of the plot to drive stakes, take a tape measure and measure the distance from one peg to another across the length and breadth of the land. As a rule, it is sufficient to make a measurement on one side length and one side of the width. since opposite sides are equal.

Write down on a sheet of paper the length and width. Assume that the length of your parcel is equal to 42 meters and width of 21 meters.
Calculate the square footage. You can use the knowledge of geometry and calculation by the formula of rectangle area. Area (S) of the rectangle, we recall, is equal to the product of the lengths of its sides. Thus, 42x21 = 882. S our area is equal to 882 square meters.
The area is calculated, it is equal to 882 square meters. It is known from the definition, that weaving is one hundred square meters. In order to know how many acres in your area of this square (882 square meters)perform the following mathematical calculations.
Divide the area of your site that you found in square meters per hundred. Thus, in response, you know, how many acres is your site. So, in our example, you 882 to divide by 100 and get of 8.82 acres, but of 8.82 acres, as noted earlier, this is the same as that of 8.82 Ara.
If the area of your lot is over 100 acres, there is a need to introduce another unit of measure is hectare. 100 acres will be equal to one hectare. Thus, in the case that the area of your lot is 10,000 square meters, respectively, it will be equal to 100 acres or 1 hectare.
Remember, the number of acres does not depend on the geometry of the section (oval, square, rectangle), it depends only on the square. Thus, if your site is round, for example, the order of the calculations is preserved. First calculate the total area of the plot, and then by dividing it by 100 will convert this area to acres.