Fish Size Library

This chart reflects the average weight of stream trout in freshwater for each given length in inches. It is meant as a guideline only.

These averages relate to Brook, Brown & Rainbow trout found in freshwater in the US and Canada. Generally speaking, for fish of the same length, a Brook Trout will be the heaviest, followed by the Brown, with Rainbow Trout averaging the lightest; but all are within a few ounces of one another.

Length in inches	Average weight
8"	5 oz
9"	5.5 oz
10"	6 oz
11"	8 oz
12"	10 oz
13"	12 oz
14"	1 lb
15"	1.3 lbs
16"	1.75 lbs
17"	2 lbs
18"	2.25 lbs
19"	2. 75 lbs
20"	3 lbs
21"	3.5 lbs
22"	4 lbs
23"	4.75 lbs
24"	5 lbs
25"	6 lbs
26"	6.5 lbs *
27"	7+ lbs *
28"	8+ lbs *

* Brook Trout are generally not found in lengths over 25"

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