Trout and salmon

Chinook salmon

Oncorhynchus tshawytscha. Also called king salmon.

Length to weight chart, typical size by age, and how to photograph a chinook salmon so fishline measures it well.

Typical top length
42 in
about 30.1 lb
A 32 inch fish
13.1 lb
13 lb 2 oz
Age at 32 inches
about 4 years
rough, varies by water
Growth levels off
about age 6
gains slow to a crawl after

Chinook salmon length to weight chart

Estimated weight for a chinook salmon in average shape at each length, from the formula W = L^3.05 / 2,970 (W in pounds, L in inches). It is the same relationship fishline uses when it measures a chinook salmon from a photo.

Chinook salmon length to weight chart
LengthWeightRough age
14 in1.1 lb1 to 2 years
16 in1.6 lb1 to 2 years
18 in2.3 lb1 to 2 years
20 in3.1 lb1 to 2 years
22 in4.2 lbabout 2 years
24 in5.5 lb2 to 3 years
26 in7.0 lb2 to 3 years
28 in8.7 lbabout 3 years
30 in10.8 lb3 to 4 years
32 in13.1 lbabout 4 years
34 in15.8 lb4 to 5 years
36 in18.8 lb5 to 6 years
38 in22.2 lb6+ years
40 in25.9 lb6+ years
42 in30.1 lb6+ years
44 in34.7 lb6+ years

Total length, nose to the tip of the pinched tail. Weights are for a chinook salmon in average shape. A fat fish, like a female before the spawn, weighs more and a thin one less, which a girth measurement picks up. Rows past 42 inches are bigger than typical for the species.

Size by age

fishline's growth model puts a typical chinook salmon at around 42 inches when fully grown, with most of its growth done by about age 6. Younger fish add length fast; older fish mostly add weight.

Age from length is rough. Fish in warm water with plenty to eat grow faster than this, and fish in cold or crowded water grow slower. For a quick estimate from any length, use the fish age calculator.

Typical chinook salmon size by age
AgeLengthWeight
1 year12.4 in0.73 lb
2 years21.1 in3.7 lb
3 years27.3 in8.1 lb
4 years31.6 in12.7 lb
5 years34.7 in16.8 lb
6 years36.9 in20.2 lb

From a von Bertalanffy growth curve. Fish in warm, food-rich water grow faster than this and fish in cold or crowded water grow slower, so treat every row as a rough middle.

Weigh your chinook salmon

Enter the length, and the girth if you taped it, for an estimate on your fish.

Total length: nose to the tip of the tail, with the tail pinched closed.

A soft tape around the body just ahead of the dorsal fin. It tells a fat fish from a thin one.

Enter a lengthPick the species and type the length in inches. The weight shows up here, with the formula behind it and a rough age.

Photo tips for chinook salmon

fishline reads length from the photo using whatever is in frame for scale, so a clean, side-on shot gives the tightest number.

  1. 1Keep the fish wet and low. Cradle it just above the water with one hand under the belly and one near the tail, side-on to the camera.
  2. 2Silver sides throw glare. Put the sun behind you or off to one side, and skip the flash when the fish is right in front of the lens.
  3. 3A wet measuring board or a net with printed marks gives fishline the tightest read. Your hand in the shot works too.

More in how to take a fish photo that measures well.

Or skip the tape. Snap a photo and fishline measures it.

Species, length and weight from one photo. 5 free measurements every month.

Measure a fish free