If you’re a fisherman, you may want to estimate the weight of a fish before releasing it or keeping it for the plate. This is where a fish weight calculator can come in handy. It’s a simple tool that allows you to estimate the weight of a fish based on its length and girth.
To use the fish weight calculator, all you need to do is measure the length and girth of the fish. The length is measured from the tip of the nose to the tip of the tail, while the girth is measured around the thickest part of the fish’s body. Once you have these measurements, simply enter them into the calculator and it will use a formula to estimate the weight of the fish.
For example, if you’ve caught a Kingfish, you can use the following formula to calculate its weight:
Weight (in kilograms) = (length (in centimeters) x girth (in centimeters) x girth (in centimeters)) / 1140
After measuring the length and girth of the kingfish, plug in the numbers to get an estimated weight. For instance, if the kingfish is 50 cm long and has a girth of 25 cm, its estimated weight would be:
Weight (in kilograms) = (50 cm x 25 cm x 25 cm) / 1140
Therefore, the estimated weight of this Kingfish would be approximately 2.5 kilograms.
The formulas for calculating the weight of the most commonly caught fish species in New Zealand are:
Snapper: Weight (in kilograms) = (length (in centimeters) x girth (in centimeters) x girth (in centimeters)) / 800
Kingfish: Weight (in kilograms) = (length (in centimeters) x girth (in centimeters) x girth (in centimeters)) / 1140
Trevally: Weight (in kilograms) = (length (in centimeters) x girth (in centimeters)) / 600
Kahawai: Weight (in kilograms) = (length (in centimeters) x girth (in centimeters)) / 500
John dory: Weight (in kilograms) = (length (in centimeters) x girth (in centimeters)) / 700
These formulas are only approximate, and the actual weight of a fish may vary depending on various factors, such as its age, condition, and whether it has been gutted or not. It is also important to note that these formulas are specific to New Zealand fish species, and may not be applicable to fish from other regions.
We have added fish weight estimate calculators for the most commonly caught species, but for ease of use have only used the fish length as a measure (using an average girth measurement). See the calculators for Snapper, Kingfish, John Dory, Blue Cod, Tarakihi or Hapuka.
