Calculating The Weight of a Fish

If you've ever fished with another fishing addict, you have asked the question a million times. "How much you think this fish weighs?"

It could be a thirty pound snook or a three pound sheepshead, but you gotta ask your friend what he or she THINKS it weighs. Lose one, and you can say it weighed anything you want to say; you never saw it, for God's sake. But if you get one in the boat, there's actually a fairly reliable way to weigh your fish. Visually and with a ruler.

This trick works WAY better with a sewing ruler like your mom used to have. If you don't have a 'ribbon' measuring tape, or one that you can somehow wrap around the widest part of the fish (Called the Girth), use a leader long enough to measure the fish's length, and mark the width by pinching the place the mark is and measuring on the decal tape you have on the inside of your boat -- or any legal measuring device.

How Big was that fish?

3 Easy Steps to Calculate the weight of a fish.

  1. Wrap that tape or leader around the thickest part of the fish. Multiply it times itself.


  2. Measure the length of the fish. Use it to multiply the value you got from #1


  3. Take that number (the fat part times itself x the length of the fish) and divide it by 800

    (GIRTH x GIRTH) x length/800

Do this fast, and with wet hands. You can do it while the fish is in the water if you're good. Try it till you GET good, and you'll be a better guardian of the fish we're all so in love with chasing around in the dark, cold, heat of summer, and anywhere else we think we're gonna be lucky enough to have one pull our lines.

So let's say you caught a snook, You take a leader and wrap it around the thick part -- right behind the gills (usually, or a little closer to the Dorsal fin. That's the main fin at the top of the fish that hurts you BAD if it sticks you).

It's 24 inches. Multiply 24 inches times itself, and you come up with 576.

<p">Measure the snook. It's 28 inches long. Multiply 576 x 28. You get 16,128. Divide it by 800?

Your snook weighed just over 20 pounds. Point-one-six over twenty pounds, to be exact.

Cool, huh? Nice snook :) Again, keep the fish IN THE WATER if you possibly can. Don't mishandle those things. Eat only what you need, not what you catch.

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