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Northern pike are long and lean, so length alone tells you a lot about their weight. This pike length-to-weight chart gives average weights you can read right at the water — useful for quick releases, since big pike are best kept wet and handled fast.

Northern pike length-to-weight chart

Length	Average weight
20″	2.29 lb
22″	3.05 lb
24″	3.95 lb
26″	5.02 lb
28″	6.27 lb
30″	7.71 lb
32″	9.36 lb
34″	11.2 lb
36″	13.3 lb
38″	15.7 lb
40″	18.3 lb
42″	21.2 lb
44″	24.4 lb

These values use weight (lb) = length³ ÷ 3,500 (length in inches), which tracks Wisconsin DNR trophy-converter figures closely — for example a 24-inch pike near 3.9 lb and a 40-inch pike near 18 lb.

What’s an average pike — and what’s a trophy?

Most pike anglers catch run 20–30 inches and 2 to 5 pounds. The magic benchmark almost everyone chases is the 40-inch pike, and 40+ inches or 20+ pounds is widely considered trophy class. Get one of those and you’ve caught a fish most anglers never will.

The IGFA all-tackle world record is a staggering 55 lb 1 oz fish from Germany in 1986 — a reminder that European and far-northern waters grow pike to sizes North American fish rarely reach.

Put a number on your exact fish (worked example)

Because pike are built like torpedoes, two 36-inchers can carry very different weight depending on how “fat” they are. Girth settles it:

Weight (lb) = Length × Girth² ÷ 800

A 40-inch pike with a 20-inch girth comes out to 40 × 20 × 20 ÷ 800 = 20 lb — a well-conditioned fish sitting a bit above the 18.3 lb length-only average. A skinnier 40-incher with a 17-inch girth would weigh closer to 14–15 lb. That spread is exactly why girth matters. Measure both and let the free fish weight calculator handle it, then check how to estimate a fish’s weight for tips.

Why two pike of the same length weigh differently

Pre-spawn, right after ice-out, is the trophy season: big females move into shallow bays heavy with eggs and are catchable even from shore for a few weeks. Diet plays a huge role too — pike are aggressive predators that eat prey up to a third of their own length, so a fish gorging on perch and suckers packs on weight fast. Body condition and region do the rest.

Where and when to find bigger pike

Pike are adaptable cool-water fish found in nearly every water type across the northern U.S. and Canada, but they favor weedy, vegetated shallows and bays as ambush cover, sliding deeper and cooler as summer water warms. The classic setup is a weed edge near a drop-off. One non-negotiable: pike have a mouth full of backward-slanting teeth and razor-edged gill plates, so a wire or heavy fluorocarbon leader is essential to avoid bite-offs, and long pliers or a jaw spreader make for safe, quick unhooking.

Northern pike weight FAQ

How much does a 40-inch northern pike weigh? About 18 pounds on average, though a heavy pre-spawn female with a big girth can hit 20+.

What’s a trophy northern pike? 40+ inches or 20+ pounds is the widely used trophy benchmark.

Do I really need a leader for pike? Yes — their teeth cut straight through mono and light fluoro. Use a wire or heavy fluorocarbon leader every time.

Related from Fishing Toolbox

• Walleye Length to Weight Chart
• How to Estimate a Fish’s Weight Without a Scale

Wondering what your walleye weighs? This walleye length-to-weight chart gives a fast, scale-free estimate for a fish in average condition — especially handy on slot-limit waters and for quick catch-and-release decisions when you don’t want to keep a big female out of the water.

Walleye length-to-weight chart

Length	Average weight
14″	1.02 lb
15″	1.25 lb
16″	1.52 lb
17″	1.82 lb
18″	2.16 lb
19″	2.54 lb
20″	2.96 lb
21″	3.43 lb
22″	3.94 lb
23″	4.5 lb
24″	5.12 lb
26″	6.51 lb
28″	8.13 lb
30″	10 lb

These figures use the standard walleye length-only formula — weight (lb) = length³ ÷ 2,700 (length in inches) — the method commonly cited by In-Fisherman and fisheries sources.

What’s an average walleye — and what’s a trophy?

Most walleye that come over the gunwale run 14–20 inches and 1 to 3 pounds. A well-grown adult is roughly 15–25 inches and 2 to 7 pounds. Anglers widely treat 25 inches (or about 8–10 lbs) as trophy class, and a 30-inch walleye is genuinely exceptional — a fish-of-a-lifetime for most.

The long-standing IGFA all-tackle record is a 25-pounder from Old Hickory Lake, Tennessee, in 1960. Worth knowing: that record is disputed — IGFA removed it in 1996 over authenticity questions and later reinstated it — so treat it as the widely cited mark rather than an uncontested one.

Put a number on your exact fish (worked example)

Length-only charts can’t tell a lean summer eye from a fat pre-spawn hen. Girth can. Use:

Weight (lb) = Length × Girth² ÷ 800

A 24-inch walleye with a 14-inch girth works out to 24 × 14 × 14 ÷ 800 = 5.9 lb — noticeably above the 5.12 lb the length-only chart predicts, because this is a well-fed, deep-bodied fish. Measure both numbers and let our free fish weight calculator do the math; it’s typically accurate within 5–10%. See how to estimate a fish’s weight if you’re new to it.

Why two walleye of the same length weigh differently

Season is the big one: pre-spawn females in early spring are heavy with eggs and at their peak weight, and the biggest fish of the year usually come from that window. Forage drives condition too — walleye keyed on abundant yellow perch or gizzard shad fatten up fast. Deep-bodied individuals and regional genetics do the rest, which is why a chart is a starting point, not the last word.

Where and when to find bigger walleye

Walleye are a cool-water species that live in large lakes, reservoirs, and rivers with hard bottoms — gravel, rock, and clay. Their glassy, light-gathering eyes (the source of the name) give them a low-light edge, so they feed best at dawn, dusk, after dark, and under a good “walleye chop” or in stained water. By day they slide deeper or into shade, often 20–60 feet down. The prime trophy window is early spring, pre-spawn, when big females stage over rocky shoals and near tributary mouths.

Walleye weight FAQ

How much does a 24-inch walleye weigh? About 5 pounds in average condition; a fat pre-spawn female can push closer to 6.

What size walleye is a trophy? Most anglers call 25+ inches or roughly 8–10 pounds a trophy. A 30-incher is rare.

Why is my walleye lighter than the chart says? Post-spawn and mid-summer fish are often lean. Measure girth and use the calculator for a true, fish-specific weight.

Related from Fishing Toolbox

• Northern Pike Length to Weight Chart
• How to Estimate a Fish’s Weight Without a Scale

Smallmouth fight well above their weight — but how much do they actually weigh? Use this smallmouth bass length-to-weight chart to estimate your catch from its length, whether you’re culling in a tournament or just curious about that river bronzeback.

Smallmouth Bass length-to-weight chart

Length	Average weight
10″	0.63 lb
11″	0.83 lb
12″	1.08 lb
13″	1.37 lb
14″	1.72 lb
15″	2.11 lb
16″	2.56 lb
17″	3.07 lb
18″	3.65 lb
19″	4.29 lb
20″	5 lb
21″	5.79 lb
22″	6.66 lb

These values use the standard smallmouth formula, weight (lb) = length³ ÷ 1,600 (length in inches), which closely tracks published In-Fisherman data for a fish in average condition.

What’s an average smallmouth — and what’s a trophy?

Most keeper smallmouth run 12–16 inches and about 1–2 pounds, with a 3–4 lb fish being a “good one” in most waters. Anglers widely treat 20 inches or 5 pounds as trophy class; on premier fisheries like the Great Lakes and St. Lawrence, the bar rises to 6 lb+. (These are angler conventions, not official standards.) The IGFA all-tackle record is 11 lb 15 oz, caught at Dale Hollow Lake on the Tennessee–Kentucky line in 1955 — a record briefly disqualified in the 1990s and then formally reinstated in 2005.

Put a number on your exact fish (worked example)

Length-only charts can’t tell a lean river fish from a chunky lake bronzeback. Girth can:

Weight (lb) = Length × Girth² ÷ 800

An 18-inch smallmouth with a 13-inch girth works out to 18 × 13 × 13 ÷ 800 = 3.8 lb, a touch above the 3.65 lb the length-only chart predicts — a well-fed fish. Measure both and let the free fish weight calculator do it (usually within 5–10%); see how to estimate a fish’s weight if you’re new to it.

Why two smallmouth of the same length weigh differently

Pre-spawn females in late spring carry eggs and hit their peak weight. Forage matters too — smallmouth gorged on crayfish and baitfish run heavier than lean current-fighting river fish. Body depth and region round it out, which is why the chart is a starting point.

Where and when to find bigger smallmouth

Smallmouth love cool, clear, oxygen-rich water with rock — boulder-strewn lake shorelines, reservoir points, and gravel runs and pools in rivers, most active around 68–72°F. Because crayfish are a signature forage, crayfish-imitating tubes, jigs, and soft plastics worked on rocky bottoms are money. The trophy window is pre-spawn/early spawn.

Smallmouth bass weight FAQ

How much does a 20-inch smallmouth weigh? About 5 pounds in average condition — a genuine trophy in most waters.

What’s a trophy smallmouth bass? Generally 20 inches or 5 lb; 6 lb+ on top-tier fisheries.

Why do smallmouth feel heavier than they weigh? They’re famously strong fighters that use current and aerial jumps — a 3-pounder fights like a bigger fish.

Related from Fishing Toolbox

• Largemouth Bass Length to Weight Chart
• How to Estimate a Fish’s Weight Without a Scale

Caught a nice largemouth and want to know what it weighs without a scale? This largemouth bass length-to-weight chart gives the average weight for a fish in typical condition — find the length, read across, and you’ve got a solid estimate for catch-and-release, tournament culling, or just settling a debate at the ramp.

Largemouth bass length-to-weight chart

Length	Average weight
10″	0.49 lb
11″	0.66 lb
12″	0.9 lb
13″	1.15 lb
14″	1.47 lb
15″	1.83 lb
16″	2.25 lb
17″	2.73 lb
18″	3.28 lb
19″	3.89 lb
20″	4.59 lb
21″	5.36 lb
22″	6.22 lb
23″	7.17 lb
24″	8.21 lb

These figures follow widely published largemouth bass data (In-Fisherman and state fisheries agencies) for a fish in average condition. They’re length-only averages, so treat them as a starting point rather than an exact reading.

What’s an average bass — and what’s a trophy?

Most largemouth an average angler catches run 12–18 inches and about 1 to 4.5 pounds, with a 16-incher (around 2.25 lb) being a very typical “good” fish. A bass over 5 pounds is a big one in most of the country, and true trophies run 7 to 10+ pounds. Double-digit fish are largely a warm-water and Florida-strain phenomenon — the Florida subspecies simply grows bigger than the northern largemouth. Keep in mind “trophy” isn’t an official standard; it’s a regional convention, so a 5-lb fish that’s a giant up north is merely nice in Florida or Texas.

For perspective, the IGFA all-tackle world record is 22 lb 4 oz, caught by George Perry in Georgia back in 1932 — one of the most famous records in all of fishing. It was tied (not broken) by a 22 lb 5 oz fish from Japan in 2009, which didn’t exceed Perry’s mark by the required margin.

Put a number on your exact fish (worked example)

The chart is a length-only average, but girth — the distance around the fish at its fattest point — is what separates a skinny bass from a tank. The classic length-and-girth formula is:

Weight (lb) = Length × Girth² ÷ 800

Say you land a 19-inch largemouth with a 13-inch girth. The chart says a 19-incher averages 3.89 lb, but run the numbers: 19 × 13 × 13 ÷ 800 = 4.0 lb. That pot-bellied pre-spawn female is carrying a little extra over the length-only average — exactly the kind of fish the girth measurement catches.

Drop your own length and girth into our free fish weight calculator and it does this instantly, usually landing within 5–10% of the scale. New to measuring girth? Our guide on how to estimate a fish’s weight walks through it.

Why two bass of the same length weigh differently

A 19-inch bass in March and a 19-inch bass in August can differ by a pound or more. The biggest factor is the spawn: pre-spawn females in early spring are the heaviest of the year, gorging to build energy and loaded with eggs. Forage matters too — a bass fattened on a rich diet of bluegill and shad carries more weight than one scraping by. Genetics (Florida vs. northern strain) and simple body depth round it out.

Where and when to find bigger largemouth

Largemouth are warm-water, structure-oriented ambush predators. Look for them tight to cover — weed beds, sunken logs, brush, standing timber, docks — in clear, warm, vegetated lakes, ponds, and slow river backwaters, most active when water sits roughly in the 65–85°F range. Adults key on sunfish and crayfish, so areas holding bluegill are prime. The trophy window is pre-spawn, early spring, when the year’s biggest females push shallow to feed.

Largemouth bass weight FAQ

How much does a 20-inch largemouth bass weigh? About 4.6 pounds in average condition, though a deep-bodied or pre-spawn fish can top 5.

What’s considered a trophy largemouth bass? Generally 7+ pounds, though anything over 5 lbs is a big fish in most northern and midwestern waters.

Is length or girth more accurate for weight? Girth. Two bass the same length can vary 20%+ in weight, and only girth captures that. Use the calculator for a fish-specific number.

Related from Fishing Toolbox

• Smallmouth Bass Length to Weight Chart
• How to Estimate a Fish’s Weight Without a Scale

Ask experienced anglers when they fish and most will say the same thing: first light and last light. The low-light windows around sunrise and sunset consistently produce more and bigger fish. Here’s why — and how to pinpoint those windows wherever you fish.

Low light tips the odds toward predators

Many gamefish are ambush predators with excellent low-light vision. At dawn and dusk they can see their prey while baitfish are at a disadvantage, so predators move shallow and hunt aggressively. The dim light also makes wary fish bolder — they’ll feed in shallow, exposed water they’d avoid under a bright midday sun.

Cooler, calmer, and more active

In warm months, the cooler water of early morning and evening is more comfortable for fish, nudging their metabolism toward feeding. Wind often lays down at these times too, and the whole food chain tends to get active at once — insects, baitfish, then the predators that eat them. It’s a daily feeding window, not just a lighting trick.

How to find your windows

A good rule is to be on the water and casting from about an hour before sunrise through the first hour of daylight, and again from an hour before sunset into dusk. Because sunrise and sunset shift through the season and depend on your exact location, it pays to look up the real times rather than guess.

Don’t ignore the rest of the day

Low light is a reliable edge, not a hard rule. Overcast days can extend the bite for hours, cold fronts can shut it down even at dawn, and night fishing shines in summer heat. Treat sunrise and sunset as your highest-percentage windows, then adjust to the weather in front of you.

Get exact times for your spot

Our free sunrise and sunset tool gives the precise sun times and prime bite windows for your location and date — so you know exactly when to launch the boat.

Related from Fishing Toolbox

• The Best Water Temperature for Every Gamefish
• How to Estimate a Fish’s Weight Without a Scale

Fish are cold-blooded, so water temperature controls almost everything they do — how fast their metabolism runs, when they spawn, and how aggressively they feed. Learn each species’ preferred range and you’ll know where to look and when they’ll bite.

Why temperature drives the bite

Within a species’ comfort zone, metabolism is high and fish feed hard to fuel it. Too cold and they turn sluggish; too warm and they get stressed and seek cooler, deeper water or shade. Find the temperature band a fish prefers and you’ve narrowed down both their location and their willingness to eat.

Preferred ranges by species

• Largemouth bass: most active 65–80 °F, peak around 72–78 °F
• Smallmouth bass: 60–75 °F, peak 65–70 °F
• Walleye: 55–70 °F, peak 60–65 °F
• Northern pike: 55–70 °F, peak 60–65 °F
• Trout (rainbow/brown): roughly 52–64 °F, peak 55–60 °F
• Crappie: 58–72 °F, peak 65–70 °F
• Channel catfish: 70–85 °F

Cool-water species like trout and walleye sit at the lower end; warm-water fish like catfish and bluegill prefer the upper end. Fish still feed outside these bands — just less aggressively.

Reading the seasons

Spring warming pulls fish shallow to feed and spawn as the water climbs into their preferred range. Midsummer heat can push warm-water fish deep during the day and turn the best bite to dawn and dusk. Fall cooling triggers heavy feeding before winter. Tracking water temperature through the year tells you which stage you’re in.

Measure it where it matters

Surface temperature from your boat’s gauge is a starting point, but fish often hold deeper where it’s cooler. A clip-on thermometer or a depth/temp probe shows you the temperature at the level fish are actually using, especially in summer when the water layers.

See which fish are active now

Want a quick read on your lake? Enter the current water temperature into our free water temperature species guide and it instantly shows which gamefish are in their prime, active, or slow range — so you can target whatever’s feeding hardest today.

Related from Fishing Toolbox

• Why Dawn and Dusk Are the Best Times to Fish
• Smallmouth Bass Length to Weight Chart

Ever notice your reel is rated for “200 yds of 12 lb mono,” but you want to fill it with braid — and have no idea how much will fit? Line capacity comes down to one thing: diameter. Here’s how to figure out exactly how much of any line your reel will hold.

Capacity is about diameter, not pound-test

A spool holds a fixed volume of line. What fills that volume is the line’s thickness, not its strength. Braid is far thinner than mono of the same pound-test, which is why a reel that holds 200 yards of 12 lb mono might swallow 400-plus yards of 30 lb braid. The rated capacity printed on the reel is just one example based on one line diameter.

The formula

Because capacity scales with the square of the diameter, you can convert the rated capacity to any line you like:

New length = Rated length × (Rated diameter ÷ New diameter)²

Diameter in millimeters is printed on most spools and boxes. Mono and fluorocarbon typically run 0.25–0.35 mm; braid is usually 0.12–0.20 mm for similar strengths.

A worked example

Suppose your reel is rated for 200 yards of line at 0.30 mm, and you want to spool 0.17 mm braid. Plug it in: 200 × (0.30 ÷ 0.17)² = 200 × 3.11 ≈ 620 yards. That thin braid more than triples your capacity — usually far more than you need, which is where backing comes in.

Use backing so you don’t waste line

If the math says your reel holds 600 yards of braid but you’ll never cast past 150, don’t spool 600 yards of expensive braid. Lay down a base of cheap mono “backing” first, then top it with the amount of braid you’ll actually use. This fills the spool to the proper level — which matters, because a properly filled spool casts farther and manages line better than an underfilled one.

Figure your capacity in seconds

Don’t want to square diameters by hand? Our free reel line capacity calculator takes your reel’s rated capacity and the new line’s diameter and tells you how much will fit — perfect for planning a respool before you buy.

Related from Fishing Toolbox

• How to Set Your Fishing Drag the Right Way
• How to Read Lead Core Line Depth by Color

Lead core line is one of the simplest ways to get a lure down to fish without downriggers or heavy weights — and the colors aren’t just for looks. Each color tells you how much line is out, which tells you roughly how deep your lure is running. Here’s how to read it.

What lead core line is

Lead core is a braided or woven line with a soft lead wire running through the center. That weight makes it sink as you let it out behind a moving boat. The line is dyed in repeating 10-yard segments, each a different color, so you can count how many segments — “colors” — you’ve deployed.

The “rule of fives”

The classic rule of thumb for standard 18 lb lead core is about 5 feet of depth per color at a trolling speed near 2 mph. Each color is 30 feet (10 yards) of line, so a full core of ten colors is 300 feet of lead. Let out five colors and you’re running roughly 25 feet down; let out eight and you’re near 40 feet.

Speed changes everything

Depth per color is not fixed — trolling speed has a huge effect. Slow down and the line sinks deeper, up to five or six feet per color. Speed up and the line planes higher in the water, averaging closer to two or three feet per color. Even a tenth of a mile per hour makes a measurable difference, which is why consistent boat speed matters when you’re trying to repeat a depth that’s producing fish.

Counting colors as you go

Let line out steadily and count each color change as it leaves the reel. Many anglers note the depth a fish hit by remembering how many colors were out, then return to that exact count. Adding a monofilament or fluorocarbon leader between the lead core and the lure keeps the heavy line away from the bait and gives a more natural presentation — just remember the leader adds a little extra depth and distance.

Standard vs thin lead core

Newer thin-diameter lead cores cut through the water with less resistance and sink faster — often around seven feet per color instead of five. If you switch line types, your old color-to-depth math changes, so recalibrate rather than assuming the same numbers.

Estimate your depth instantly

Skip the mental math on the water. Our free trolling depth calculator turns colors out, speed, and line type into an estimated running depth in seconds — a great starting point before you fine-tune with a depth finder.

Related from Fishing Toolbox

• Braid vs Mono: How Much Line Really Fits on Your Reel
• How to Set Your Fishing Drag the Right Way

Drag is the quiet hero of every fight. Set it well and a big fish tires itself out against smooth, steady pressure. Set it wrong and you either snap the line on the hookset or watch a trophy throw the hook because there was never enough tension. Here’s how to dial it in every time.

What drag actually does

Your reel’s drag is a friction system that lets line slip out under load before it reaches its breaking point. When a fish surges, the drag gives line instead of letting the rod and line take the full force. The goal is to apply the most pressure you can without risking a break — enough to control the fish, not so much that a sudden run pops the line.

The 25–33% rule

A reliable starting point is to set your drag to one-quarter to one-third of your line’s rated breaking strength. So for 20 lb line, that’s roughly 5 to 6.6 lb of drag pressure. Starting at the lower end gives you a safety margin; you can always add pressure during the fight, but you can’t take back a break.

How to set it with a scale

Guessing by pulling line off the spool with your hand is better than nothing, but a simple spring scale makes it exact. Tie your line to the scale, hold the rod at the angle you’d fight a fish (tip up, loaded), and pull until line just begins to slip. Adjust the drag knob or star until the scale reads about a quarter to a third of your line test. Do this with the same knot and line you’ll actually fish.

When to back off

• Light leaders: if your leader is weaker than your main line, set drag to the leader’s strength, not the main line’s.
• Fish near structure: heavy cover can mean you need to lighten up so a head-shake doesn’t snap you off — or tighten down to turn fish, depending on your strategy.
• Treble hooks and soft mouths: species like crappie or trout tear out easily; a lighter drag protects the hook hold.
• Near the boat: a fish’s final lunge boatside breaks more line than the whole fight. Be ready to thumb the spool or ease the drag.

Common mistakes

The two biggest errors are fishing with the drag cranked all the way down “so the fish can’t take line,” and never checking it after it’s been sitting. Drag washers settle and stiffen over time, and a reel left fully tightened can develop a sticky, jerky drag. Back the drag off when you store a reel, and re-check the setting at the start of every trip.

Let the calculator do the math

Not sure what a quarter to a third of your line works out to? Our free drag setting calculator gives you the recommended drag range the moment you enter your line’s pound-test — so you know exactly what to aim for on the scale.

Related from Fishing Toolbox

• Braid vs Mono: How Much Line Really Fits on Your Reel
• How to Estimate a Fish’s Weight Without a Scale

Whether you’re chasing a personal best, fishing a catch-and-release tournament, or just settling a friendly bet at the boat ramp, knowing what your fish weighs matters. But carrying a scale isn’t always practical, and hanging a fish on one long enough to get a reading is hard on a fish you plan to release. The good news: you can get a reliable weight estimate with nothing but a tape measure and a little math.

The formula that actually works

For most fish, weight is closely tied to two measurements: length and girth. The formula anglers have trusted for decades is:

Weight (lb) = (Length × Girth × Girth) ÷ 800 — with length and girth both measured in inches.

Girth is the key. Two fish of the same length can weigh very differently — a fat, well-fed bass carries far more than a long, skinny one. Because girth captures how heavy-bodied a fish is, this method is usually accurate to within 5–10% of the true weight for a fish in average condition.

How to measure your fish

Length: Lay the fish flat and measure from the tip of the nose to the end of the tail. Keep the tape straight along the body.

Girth: This is the distance all the way around the fish at its fattest point — usually just behind the gills and pectoral fins. Wrap a flexible tape (or a piece of fishing line you measure afterward) snugly around the body. Don’t cinch it tight; just bring it flush against the fish.

Match the formula to your species

The 800 divisor works well for thicker-bodied fish. Leaner, more streamlined species carry less weight for their length, so they use a slightly larger divisor of about 900:

• Divide by 800: largemouth and smallmouth bass, catfish, panfish
• Divide by 900: trout, walleye, northern pike, muskie

Using the right divisor keeps slim fish from being overestimated and heavy-bodied fish from being shortchanged.

A worked example

Say you land a largemouth bass that’s 18 inches long with a 12-inch girth. Plug it in: (18 × 12 × 12) ÷ 800 = 2,592 ÷ 800 = 3.24 lb. A quick, repeatable number — no scale required.

No way to measure girth? Estimate from length

If all you have is a length, you can still ballpark the weight, but expect it to be rougher — a length-only estimate has to assume an average body shape, and real fish are fatter or thinner than average. Treat it as a guide and add girth whenever you can for a number you can actually trust.

Tips for a more accurate estimate

• Measure quickly and keep the fish wet and calm, especially if you’re releasing it.
• Measure girth at the widest point, not back toward the tail.
• Pre-spawn females run heavy — a fish full of eggs can weigh 10–20% more than the formula suggests.
• For an official record, an estimate never counts; only a certified scale does. The formula is for everyday use and release fishing.

Skip the math — use the free calculator

Don’t want to do arithmetic with cold, wet hands? Our free fish weight calculator does it for you: choose your species, enter length and girth, and it instantly returns the weight in pounds, ounces, and kilograms — using the exact formula above, with the right divisor already built in for each species.

Related from Fishing Toolbox

• Smallmouth Bass Length to Weight Chart
• Largemouth Bass Length to Weight Chart