Weight calculators

[catman529]

Seems each weight calculator on the internet is different and not very accurate... sometimes even 5 pounds off or more... I know because I weighed my carp 23 pounds and also had length & girth measurements. I think I will start recording all my carp's weights, length and girth so I can come up with my own formula for carp and see how accurate I can make it (including adjustments for fish fatness and tail size).

Anyone know of any good formulas that are at least half decently accurate? Or is it near-impossible to make one that is really good. I was thinking, take the measurement of the length with the tail, and the length without the tail, because some tails are bigger than others and could skew the weight calculation.

Just a thought. Got to put the stuff down in my new fishing log...

 

[rsimms]

I regularly use length x girth x girth / 800 = weight

I have cross-checked it with catfish and bass NUMEROUS times and have always found it to be amazingly accurate.

Example - Smallmouth Bass 21-inches long with 14-inch girth

21 x 14 x 14 = 4,116 divided by 800 = 5.145 lbs.

That formula won't work on long skinny fish such as walleye, sauger, etc. But on bass and cats, it sure works for me.

 

[easy45]

I think I will just use a scale

 

[catman529]

I regularly use length x girth x girth / 800 = weight

I have cross-checked it with catfish and bass NUMEROUS times and have always found it to be amazingly accurate.

Example - Smallmouth Bass 21-inches long with 14-inch girth

21 x 14 x 14 = 4,116 divided by 800 = 5.145 lbs.

That formula won't work on long skinny fish such as walleye, sauger, etc. But on bass and cats, it sure works for me.

It slightly underestimated my grass carp. I found that for the 23 pounder, the number to divide by is around 748 instead of 800. I plan to record all measurements from many carp and then see how they differ and try to come up with my own variable formula.