Bonefish Weight Calculator – Estimate Weight by Length

🐟 Bonefish Weight Calculator

Estimate bonefish weight from length & girth — imperial & metric results instantly

Quick Presets
📏 Measurements (Imperial)
✅ Estimated Bonefish Weight Results
📊 Bonefish Size Quick Reference
16 lb
World Record
22 in
Avg Flats Bone
5–8 lb
Trophy Range
7.3 kg
Record (Metric)
800
Std Divisor
30 in
Record Length
G² × L
Formula Core
2–4 lb
Schoolie Range
📈 Bonefish Length vs. Estimated Weight Chart
Length (in) Length (cm) Typical Girth (in) Est. Weight (lb) Est. Weight (kg) Size Class
1435.67.50.990.45Juvenile
1640.68.51.450.66Juvenile
1845.79.52.030.92Schoolie
2050.810.52.761.25Schoolie
2255.911.03.331.51Average
2461.012.04.321.96Average
2666.013.05.492.49Trophy
2871.114.06.863.11Trophy
3076.215.08.443.83World-Class
3281.316.010.244.64World-Class
🧮 Weight Formula Comparison (22 in / 11 in girth)
Formula Equation Divisor Result (lb) Result (kg) Best For
StandardL × G² / 8008003.331.51General use
Penn FormulaL × G² / 9009002.961.34Heavier-bodied fish
IGFA AdjustedL × G² / 7507503.551.61Record claims
Length OnlyL³ / 160016003.651.66No girth available
🎣 Recommended Gear by Bonefish Weight Class
Weight Class Est. Weight Rod Weight Line Class Fly Line Leader Length
JuvenileUnder 2 lb / 0.9 kg4–5 wt4–6 lbWF-4F9 ft
Schoolie2–4 lb / 0.9–1.8 kg6–7 wt8–10 lbWF-6F9–12 ft
Average4–6 lb / 1.8–2.7 kg7–8 wt10–12 lbWF-8F12 ft
Trophy6–10 lb / 2.7–4.5 kg8–9 wt12–16 lbWF-9F12–14 ft
World-Class10 lb+ / 4.5 kg+9–10 wt16–20 lbWF-10F14–16 ft
💡 Calculation Tips
📏 Measure Girth Accurately: Girth (G) is squared in the formula, so even small measurement errors have a big impact on the final weight estimate. Always measure at the widest point of the fish’s body, just behind the pectoral fins. Use a flexible cloth tape measure while the fish is in the water for best results.
🧮 Which Formula to Use: The Standard formula (L × G² / 800) works well for most bonefish. Use the IGFA Adjusted (/ 750) for round, well-fed fish and the Penn Formula (/ 900) for longer, leaner fish. The Length-Only formula (L³ / 1600) is a fallback when girth cannot be measured.

Bonefish are saltwater fish of medium size that feed in very shallow water. The most common of them weigh between 1 and 15 pounds but that range can change a lot based on the place where they live. It is one of the cool traits of that species, bonefish from various regions of the globe show big differences in size, mass and look.

Average bonefish reach up to 17 pounds and lengths up to 31 inches. Their whole length usually falls between 16 and 30 inches, while the body height range is 3.5 up to 6.5 inches. The average weight usually swings between 7 and 20 pounds.

Bonefish Size and Weight

Some of the common rnages point 4 up to 15 pounds for them. The most common have 3 up to 4 pounds, but in some places they can grow up to 12 up to 15 pounds.

In some regions bonefish become bigger than in others. Samples caught in Africa or Hawaii commonly pass 20 pounds. Some copies even reached 10 kilos, what matches around 21 pounds, with length up to 90 centimetres.

Even so, in many places the biggest length and weight stays around 30 inches and 14 pounds.

In the Bahamas, bonefish can pass ten pounds, although more commonly they are around a third of that mass. At Los Roques, the standard size passes 5 pounds, and some samples reach 8 up to 10 pounds. On South Andros, each angler wants the trophy ten-pound bonefish.

Four-pound bonefish could easily beet 10-pound chinook salmon in struggle; the fame about their force in fight is real.

There are charts that help to guess the weight of bonefish based on their length. Fish of 18 inches weighs about 3.5 pounds. A 22-inch sample has around 5.1 pounds.

For 28 inches, it reaches about 8.6 pounds. Bonefish of 30 inches weigh roughly 10.8 pounds, while a 34-inch version arrives at 15.6 pounds. Based on that chart, 27-inch bonefish have around 7.7 pounds.

There are also online calculators that combine length and girth to better guess the weight.

Bonefish reach sexual maturity between 3 and 4 years, usually when they measure 17 up to 19 inches. Although they already are quite big in only three years, bonefish continuously grow during the rest of their life. Their colours range from bright silver sides with a bit grayer backs to olive shade mixed with silver.

They eat crustaceans, molluscs, worms andsmall fish.

Bonefish Weight Calculator – Estimate Weight by Length

Leave a Comment