The most accurate way to measure the weight of a pig is to use a specialist pig weigh or hog scales. However, these can be expensive and if you only have a few pigs to weigh and a high degree of accuracy is not necessarily needed, we explain how to obtain a good estimate of a pigs weight using only a measuring tape and a calculator.
You will need a measuring tape similar to those used by tailors. The formula is not exact, but it comes within about three percent of the actual weight. The formula is as follows:
1. Girth measurement take the heart-girth measurement. Your measuring tape needs to go around the body just behind the front legs and over the shoulder area. As an example for you I will use the measurements of Flower. Her girth measurement is 43 inches.
2. Square the result (multiply the measurement by itself). Example: The measurement was 43 inches. 43 X 43 = 1,849.
3. Length measurement. Measure the length of your pig. Start at the top of his or her head right in between the ears and measure down to the start, or base, of the tail (not the end of the tail). Flower’s length is 39 inches.
4. Girth result x length: Take the girth measurement result (in the example above this was 1,849) and multiply that times the length of your pig. In our example this would be: 1,849 X 39 = 72,111.
5. Weight calculation: Divide this result by 400, and you’ll have a weight accurate to within about three percent. In our example: 72,111 divided by 400 = 180 pounds. Factoring in the 3% variance (5.4 pounds), this means Flower weighs between 174.6 and 185.4 pounds.
Credit for this formula goes to the Old Farmer’s Almanac 1993.