Atlantic Salmon Weight Calculator – Estimate Fish Weight by Length

🐟 Atlantic Salmon Weight Calculator

Estimate your Atlantic salmon's weight from length & girth measurements using proven formulas

Quick Presets
🔧 Calculator Settings
✅ Salmon Weight Estimate
📊 Salmon Weight Quick Reference
79.2 lb
World Record
4–8 lb
Avg Grilse
20+ lb
Trophy Class
L×G²/800
Standard Formula
📏 Length vs. Estimated Weight Table
Fork Length (in) Fork Length (cm) Est. Girth (in) Est. Weight (lb) Est. Weight (kg) Class
1640.69.61.80.8Parr/Smolt
2050.811.03.01.4Small Grilse
2461.013.05.12.3Grilse
2871.115.07.93.6Grilse
3076.216.09.64.4Grilse/Adult
3486.417.513.05.9Adult
3691.418.515.47.0Adult
40101.620.521.09.5Large Adult
44111.822.026.612.1Trophy
48121.924.034.615.7Trophy
52132.125.542.219.1Trophy
56142.227.051.023.1Record Class
🐟 Atlantic Salmon by Fish Type & Condition
Fish Type Typical Length Typical Weight Condition Factor Notes
Grilse (1SW)20–28 in / 51–71 cm3–8 lb / 1.4–3.6 kg0.95–1.001 sea-winter fish
2-Sea-Winter28–36 in / 71–91 cm8–18 lb / 3.6–8.2 kg1.00–1.05Most common adult
3-Sea-Winter36–44 in / 91–112 cm18–30 lb / 8.2–13.6 kg1.00–1.05Prime trophy fish
MSW (4+)44–56 in / 112–142 cm30–60 lb / 13.6–27.2 kg1.02–1.08Very rare, record class
Kelt (Post-Spawn)28–44 in / 71–112 cm5–14 lb / 2.3–6.4 kg0.70–0.85Emaciated, thin body
Landlocked Salmon14–26 in / 36–66 cm1–8 lb / 0.5–3.6 kg0.85–0.95Sebago/Ouananiche
Farmed Atlantic22–32 in / 56–81 cm6–15 lb / 2.7–6.8 kg1.05–1.15Stockier body shape
🎯 Girth-to-Length Ratio Reference
Body Condition Girth/Length Ratio Example: 30 in Fish Expected Girth Condition Factor
Thin / Kelt0.44–0.4830 in13.2–14.4 in0.75–0.82
Below Average0.48–0.5230 in14.4–15.6 in0.82–0.90
Average0.52–0.5630 in15.6–16.8 in0.90–1.00
Good0.56–0.6030 in16.8–18.0 in1.00–1.05
Excellent / Sea-Run0.60–0.6530 in18.0–19.5 in1.05–1.12
💡 Measurement Accuracy Tip: Always measure fork length (tip of snout to fork of tail) on a wet, flat surface. Measure girth at the widest point of the body — typically just behind the pectoral fins. Use a flexible cloth or tailor's tape. A difference of just 1 inch in girth can change the estimated weight by 10–15%.
💡 Formula Selection Guide: The standard formula (L × G² ÷ 800) works best for fresh, sea-run Atlantic salmon with a known girth. Use the length-only estimate when you cannot measure girth — it uses an average girth/length ratio of 0.54. Post-spawn kelts will weigh significantly less than the formula predicts; apply the 0.75–0.80 condition factor for accurate estimates.

Get crisp skin on fish seems easy, until you truly try that. When the fish touches the warm oil, it starts crisp well but soon it starts curling up. Then everything goes wrong; truly wrong.

The skin cooks uneven, becomes soft everywhere, and at last you have a ruined plate. The reason is, that the clamped parts of the fish do not touch the pan, so the skin never has chance to crisp right.

How to Make Fish Skin Crispy

Here comes the fish press. It does one basic task: press the fish against the bottom of the pan, so that the skin truly crisps and the whole cooks equally. Does that not sound logical?

Even so many folks believe, that one can use a newspaper weight for hamburgers. No truly, a good fish press is specially made, and it makes a big difference.

Maybe you will ask, whether one can simply take an iron pan or some random weight instead. Here is the problem: such options commonly are too heavy, spread the pressure uneven or even react with the fish. A good fish press is diferent.

It is comfortable, spreads the pressure equally over the fish, and made from stainless steel, so it does not rust, does not colour the food or damage anything tender.

One good choice is the stainless steel model by Josh Niland, that comes in some versions, including the Rainbow. The price is around 165 dollars, and it ships quickly through United States and Canada. What makes it good, is its high density (a lot of weight in a little body).

Besides that, it is easy to clean after use.

If that price seems too high, there is another way, that is worth looking into. Search old style metal weights (the simple type), that is only solid metal with a handle, without any electronics. Thrift shops and yard sales sometimes have them for little money, and they work surprisingly well for a fraction of the cost.

Now, finding the wait of fish without a scale is a whole other challenge. One formula, that works well for trout, multiplies the length by the girth, then divides by 800. You can adjust that 800 number higher or lower, depending on if your fish is heavier or lighter than normal.

No measure of girth? Estimate it using 0.58 times the length.

But here is where it gets hard, those formulas are not perfect. Long and slim fish, just like thick and shorter ones, can weigh totally different even at same length. Atlantic salmon are famous for that.

So length gives you more reliable info than weight for guessing the size of fish. Weight changes with food, but length stayspermanent.

For the best result, take a scale with a built in lip grip and attach it to the center of the bottom jaw of the fish. No grip on your scale? Attach a separate lip grip to the hook and simply subtract its weight from the result.

The best rule: return the fish to the water right after the measurement.

Atlantic Salmon Weight Calculator – Estimate Fish Weight by Length

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