How to Calculate the Weight of Your Trout

A lot of trout fishers are 'catch and release' anglers. They love the sport of trout fishing, but don't want to kill the fish. But when you catch that prize trout, you certainly want to record the length and weight and share it with photos.

But a lot of fish scales require hanging the fish by the gills - which is counter-productive to 'catch and release'. One way around this, is to guesstimate the weight using a formula.

The accepted formula for calculating the weight of a fish is this:

(length) * (girth in front of dorsal fin) * (girth behind dorsal fin) / 800 = weight of fish in pounds

Keep in mind this only an ESTIMATE and should not be considered 100% accurate.

The actual weight of the fish can only be measured by a scale. And if you're looking to get that world or state record in the books, then you will have to officially weigh your fish.

But this formula will give you an idea of whether or not a fish may qualify for the record book - which can help you make the decision on whether or not to release it.

Don't like math? Check out our fish weight calculator.