line-sizes/

Fishing line size chart

The mainline and leader pound test for every species the Rig Studio knows, on one scale from 2 to 200 lb. Then the part most charts skip: pound test is not thickness. Braid runs a fraction of mono's diameter at the same test, and rod ratings are printed for mono, so we convert every line through its own diameter table before comparing it to anything.

23 species · 13 lines and leaders · 8 rods · source: src/data/species.ts + catalog · the same numbers the studio checks

line.chart2 → 200 lb, log scale

Line pound test by species

The solid bar is the mainline window the studio accepts without a warning. The hatched tail runs to 1.5× its top, where the studio starts calling the line heavy. The thin bar under it is the leader window. Pick a fish for the full call.

Thin bar colour: wire for teeth · leader expected for abrasion · fluoro in clear water for line-shy fish · optional. Windows are pound test, any material.

line.by-species23 rows

What pound test line for each species

Under the window the studio warns that every snag and headshake becomes a coin flip; over 1.5× the top it warns that you are paying in casting distance and visibility for strength you will not use. The leader call comes from the fish's abrasion and line-shy ratings. "Our rigs" is the line the solver picked for the cheapest build that clears every engine error for that fish.

Mainline and leader pound test, leader call, reel needs and solved-rig line for each species
Species	Mainline	Leader	Reel	Our rigs spool
Brook Troutfresh	2–6 lbheavy over 9 lb	2–4 lbfluoro, clear water	1 lb drag120 yd	4 lb Berkley Trilene XLMountain Creek, Hardwater / Ice
Bluegill & Panfishfresh	2–8 lbheavy over 12 lb	noneoptional	1 lb drag120 yd	4 lb Berkley Trilene XLFarm Pond, Weedy Lake, Hardwater / Ice
Rainbow Troutfresh	2–8 lbheavy over 12 lb	2–6 lbfluoro, clear water	2 lb drag120 yd	4 lb Berkley Trilene XLFarm Pond, Clear Reservoir, Mountain Creek, River Run, Hardwater / Ice
Crappiefresh	4–10 lbheavy over 15 lb	4–8 lbfluoro, clear water	2 lb drag120 yd	4 lb Berkley Trilene XLFarm Pond, Weedy Lake, Clear Reservoir, Hardwater / Ice
Smallmouth Bassfresh	6–15 lbheavy over 23 lb	8–12 lbfluoro, clear water	4 lb drag120 yd	6 lb Berkley Trilene XLClear Reservoir, River Run, Big River Channel
Walleyefresh	6–15 lbheavy over 23 lb	8–15 lbfluoro, clear water	4 lb drag120 yd	6 lb Berkley Trilene XLWeedy Lake, Clear Reservoir, River Run, Big River Channel, Hardwater / Ice
Bonefishsalt	8–20 lbheavy over 30 lb	10–20 lbexpected	6 lb drag120 yd	8 lb Berkley Trilene XL + 12 lb fluorocarbon leaderInshore Flat
Steelheadfresh · brackish	8–20 lbheavy over 30 lb	8–15 lbfluoro, clear water	6 lb drag200 yd	8 lb Berkley Trilene XLRiver Run, Big River Channel
Speckled Troutsalt · brackish	10–20 lbheavy over 30 lb	15–25 lbfluoro, clear water	5 lb drag120 yd	10 lb Berkley Trilene XLInshore Flat, Mangrove Estuary, Jetty & Pier
Largemouth Bassfresh	8–30 lbheavy over 45 lb	10–20 lbexpected	6 lb drag120 yd	8 lb Berkley Trilene XL + 12 lb fluorocarbon leaderFarm Pond, Weedy Lake, Clear Reservoir, River Run, Big River Channel
Floundersalt · brackish	12–25 lbheavy over 38 lb	20–30 lbexpected	5 lb drag120 yd	12 lb Berkley Trilene XL + 20 lb fluorocarbon leaderOpen Surf Beach, Inshore Flat, Mangrove Estuary, Jetty & Pier
Common Carpfresh	12–30 lbheavy over 45 lb	15–25 lbfluoro, clear water	8 lb drag300 yd	12 lb Stren OriginalFarm Pond, Weedy Lake, Clear Reservoir, Big River Channel
Channel Catfishfresh	15–30 lbheavy over 45 lb	20–40 lbexpected	8 lb drag200 yd	17 lb Stren Original + 20 lb fluorocarbon leaderFarm Pond, Clear Reservoir, River Run, Big River Channel
Redfishsalt · brackish	15–40 lbheavy over 60 lb	20–40 lbexpected	10 lb drag200 yd	17 lb Stren Original + 20 lb fluorocarbon leaderOpen Surf Beach, Inshore Flat, Mangrove Estuary, Jetty & Pier
Salmon (Coho / King)salt · fresh · brackish	15–40 lbheavy over 60 lb	20–40 lbexpected	10 lb drag300 yd	15 lb Berkley Vanish + 20 lb fluorocarbon leaderRiver Run, Big River Channel
Snooksalt · brackish	20–40 lbheavy over 60 lb	30–60 lbexpected	12 lb drag200 yd	20 lb Stren Original + 30 lb fluorocarbon leaderOpen Surf Beach, Inshore Flat, Mangrove Estuary, Jetty & Pier
King Mackerelsalt	20–50 lbheavy over 75 lb	40–90 lbwire	15 lb drag300 yd	20 lb Stren Original + 40 lb wire leaderJetty & Pier, Nearshore Reef, Offshore Bluewater
Northern Pikefresh	20–50 lbheavy over 75 lb	40–90 lbwire	10 lb drag200 yd	20 lb Stren Original + 40 lb wire leaderWeedy Lake, Clear Reservoir, Hardwater / Ice
Striped Basssalt · brackish · fresh	20–50 lbheavy over 75 lb	30–60 lbexpected	12 lb drag300 yd	20 lb Stren Original + 30 lb fluorocarbon leaderClear Reservoir, Big River Channel, Open Surf Beach, Inshore Flat, Jetty & Pier
Blue Catfishfresh · brackish	30–80 lbheavy over 120 lb	50–100 lbexpected	15 lb drag300 yd	30 lb Stren Original + 50 lb fluorocarbon leaderClear Reservoir, Big River Channel
Tarponsalt · brackish	50–80 lbheavy over 120 lb	60–100 lbexpected	20 lb drag300 yd	no clean rig yet: no catalog rod is rated for this fish
Muskellungefresh	50–100 lbheavy over 150 lb	100–174 lbwire	18 lb drag300 yd	80 lb PowerPro Spectra + 135 lb wire leaderWeedy Lake, Clear Reservoir, River Run
Yellowfin Tunasalt	50–130 lbheavy over 195 lb	80–174 lbexpected	25 lb drag300 yd	no clean rig yet: no catalog rod is rated for this fish

line.diameter13 lines, mm per lb test

Line diameter chart: braid vs mono vs fluorocarbon

Each line is one product's published diameter at every test it ships in. Read across at a diameter and you get the tests that are equally thick; read up at a test and you see how far apart the materials sit. Braid is the low line on the chart: 0.28 mm at 30 lb, where 30 lb mono is 0.56 mm.

braid
mono
fluorocarbon
copolymer
wire
sold as leader

Braid to mono conversion chart

Each cell is the braid's published diameter and the mono test of the same thickness (on the Trilene curve the engine uses). That mono figure is what a rod rating actually measures, so it is the number to hold against the label on the blank.

Braid pound test to diameter and mono equivalent, by brand
Braid test	PowerPro Spectra	Sufix 832	Daiwa J-Braid
6 lb	–	0.13 mm ≈ under 4 lb mono	–
10 lb	0.15 mm ≈ under 4 lb mono	0.15 mm ≈ under 4 lb mono	0.13 mm ≈ under 4 lb mono
15 lb	0.19 mm ≈ under 4 lb mono	0.18 mm ≈ under 4 lb mono	0.16 mm ≈ under 4 lb mono
20 lb	0.23 mm ≈ 6 lb mono	0.23 mm ≈ 6 lb mono	0.18 mm ≈ under 4 lb mono
30 lb	0.28 mm ≈ 8 lb mono	0.28 mm ≈ 8 lb mono	0.24 mm ≈ 6 lb mono
40 lb	0.32 mm ≈ 11 lb mono	0.33 mm ≈ 11 lb mono	0.28 mm ≈ 8 lb mono
50 lb	0.36 mm ≈ 13 lb mono	0.36 mm ≈ 13 lb mono	0.33 mm ≈ 11 lb mono
65 lb	0.41 mm ≈ 17 lb mono	0.40 mm ≈ 16 lb mono	0.37 mm ≈ 14 lb mono
80 lb	0.46 mm ≈ 20 lb mono	0.45 mm ≈ 19 lb mono	0.42 mm ≈ 18 lb mono
100 lb	0.55 mm ≈ 29 lb mono	–	–

The other way: braid for a mono-rated rod

Heaviest braid no thicker than the mono test on the label.

Heaviest braid matching a mono rating, by brand
Mono rating	PowerPro Spectra	Sufix 832	Daiwa J-Braid
6 lb	20 lb	20 lb	30 lb
8 lb	30 lb	30 lb	40 lb
10 lb	30 lb	30 lb	40 lb
12 lb	40 lb	40 lb	50 lb
15 lb	50 lb	50 lb	65 lb
20 lb	80 lb	80 lb	80 lb

Diameters are each maker's published figures as recorded in the catalog. Thickness varies between batches and a little between colours; treat a few hundredths of a millimetre as noise.

line.on-rodover-lined · under-lined · braid-no-stretch

What line fits a rod's line rating

The studio runs three checks between mainline and rod. over-lined errors when the line's mono-equivalent passes the top of the rating: the rod becomes the fuse on a snag.under-lined warns when a non-braid line sits under 0.6× the bottom of the rating: the blank never flexes before the line pops. Braid is exempt from that one, because thin braid on a stiff blank is the point. braid-no-stretch warns on braid stronger than 2.5× the top rating, because nothing in the system gives.

Catalog rods with printed line rating and the test range of each line material that clears all three checks
Rod	Printed rating	mono that passes	fluorocarbon that passes	braid that passes
Daiwa Crossfire Ultralight5.6 ft UL spinning · ~$40	2–6 lb	4–6 lb	4–8 lb	up to 15 lb
St. Croix Triumph Spinning Rod7 ft ML spinning · ~$130	6–12 lb	4–12 lb	4–17 lb	up to 30 lb
Okuma Celilo Steelhead Float Rod10.5 ft L spinning · ~$70	6–12 lb	4–12 lb	4–17 lb	up to 30 lb
Ugly Stik GX2 Spinning Rod6.6 ft M spinning · ~$45	8–20 lb	6–20 lb	6–25 lb	up to 50 lb
St. Croix Mojo Inshore Spinning Rod7 ft M spinning · ~$220	8–20 lb	6–20 lb	6–25 lb	up to 50 lb
Shimano SLX Casting Rod7 ft MH casting · ~$100	10–20 lb	6–20 lb	8–25 lb	up to 50 lb
Dobyns Fury Heavy Casting Rod7.6 ft H casting · ~$150	15–30 lb	10–30 lb	12–30 lb	up to 65 lb
Penn Prevail III Surf Rod10 ft MH surf · ~$140	15–40 lb	10–40 lb	12–30 lb	up to 100 lb

Ranges span every catalog line of that material at every test it ships in. Fluorocarbon runs thinner than mono per test, so it reaches higher on the same rod. Braid has no floor because the under-lined check skips it. Fly rods are left out: they cast fly line, and the tippet is a leader, not a mainline.

line.materials13 items

Every line and leader in the catalog

Stretch, visibility and abrasion are the 0–10 figures the engine and the sim read: stretch sets how much of a hookset the line absorbs, visibility feeds the clear-water checks, and sinking line drags the sim's rope down while floating line bows on the surface. The long version is in braid vs mono vs fluorocarbon.

Catalog lines with material, tests, diameter range and handling figures
Line	Material	Tests	Diameter	Stretch	Visibility	Abrasion	In water
PowerPro Spectra Braided Linemainline · ~$22	braid	10–100 lb	0.15–0.55 mm	0	8	5	floats
Sufix 832 Advanced Superlinemainline · ~$27	braid	6–80 lb	0.13–0.45 mm	0	7	6	floats
Daiwa J-Braid Grand x8mainline · ~$30	braid	10–80 lb	0.13–0.42 mm	0	6	5	floats
Berkley Trilene XL Monofilamentmainline · ~$9	mono	4–30 lb	0.20–0.56 mm	10	4	5	floats
Berkley Trilene Big Gamemainline · ~$14	mono	10–80 lb	0.30–0.90 mm	10	5	6	floats
Seaguar InvizX Fluorocarbonmainline · ~$24	fluorocarbon	4–25 lb	0.17–0.43 mm	3	1	8	sinks
Berkley Vanish Fluorocarbonmainline · ~$11	fluorocarbon	4–30 lb	0.18–0.50 mm	4	1	7	sinks
Stren Original Copolymermainline · ~$10	copolymer	6–30 lb	0.22–0.54 mm	7	4	6	floats
Seaguar Blue Label Fluorocarbon Leaderleader · ~$22	fluorocarbon	6–100 lb	0.20–0.91 mm	3	1	9	sinks
Yo-Zuri HD Carbon Fluorocarbon Leaderleader · ~$14	fluorocarbon	8–80 lb	0.23–0.88 mm	3	1	8	sinks
Ande Premium Monofilament Leaderleader · ~$18	mono	20–130 lb	0.45–1.17 mm	9	5	6	floats
American Fishing Wire Surflon Micro Supreme Wireleader · ~$16	wire	26–135 lb	0.36–0.91 mm	0	7	10	sinks
Knot 2 Kinky Titanium Toothproof Leaderleader · ~$34	wire	20–174 lb	0.28–0.76 mm	0	6	10	sinks

frequently asked09

What pound test line for bass?

Largemouth 8–30 lb, smallmouth 6–15 lb. The light end is spinning gear and finesse baits; the heavy end is a casting rod in cover. Largemouth live in wood and weeds, so we expect a 10–20 lb leader; clear-water smallmouth are line-shy enough that a fluorocarbon leader matters more than the mainline test.

What pound test line for trout?

Rainbow trout 2–8 lb, brook trout 2–6 lb. Trout are among the most line-shy fish in our data (0.90 and 0.95 on a 0–1 scale), so thinner line gets more bites before any lure change does. Every solved rainbow and brook trout rig on this site spools 4 lb.

What pound test line for catfish?

Channel catfish 15–30 lb, blue catfish 30–80 lb. Both rate high for abrasion, so a leader is expected: 20–40 lb for channels and 50–100 lb for blues. Blues to 50 lb also need a reel that holds 300 yards.

What pound test line for crappie and bluegill?

Crappie 4–10 lb, bluegill 2–8 lb. Neither needs a leader for strength. Light line matters more for how a small jig falls and how a float sits than for what the fish can break.

What size braid equals 10 lb mono?

By diameter: 30 lb PowerPro Spectra (0.28 mm), 30 lb Sufix 832 (0.28 mm), 40 lb Daiwa J-Braid (0.28 mm). 10 lb Berkley Trilene XL measures 0.30 mm. At the same thickness braid carries roughly three to four times mono's pound test, and the exact figure differs by brand, which is why we convert through each line's own diameter table.

Can I put 30 lb braid on a rod rated 8–20 lb?

Yes. 30 lb PowerPro Spectra measures 0.28 mm, the diameter of about 8 lb mono, and rod ratings are printed for mono. The studio passes it on the Ugly Stik GX2 Spinning Rod. Its heaviest clean PowerPro Spectra is 50 lb: past 2.5× the 20 lb top rating (50 lb), braid with no stretch puts the whole hookset into the blank.

Is 20 lb braid stronger than 20 lb mono?

No. Pound test is the rated breaking strain, so both are sold to break near 20 lb. What differs is diameter and stretch: 20 lb PowerPro Spectra measures 0.23 mm against 0.46 mm for 20 lb Berkley Trilene XL. Thinner line casts further, cuts current better and puts more on a spool. Braid also has almost no stretch, which is why it is never measured against a rod's printed rating at face value.

How heavy should a leader be compared to the mainline?

Between 0.75× and 2× the mainline test. Under 0.75× the leader is the designed break point, which is a fair choice around snags because you lose only the terminal end. Over 2× the mainline becomes the fuse, and a snag costs you the leader, the rig and some mainline. Leader material is a separate call: wire for teeth, heavy fluorocarbon for abrasion, light fluorocarbon for clear water.

Does line diameter change how much line fits on a reel?

Yes, roughly with the square of the diameter ratio. Line half as thick fits about four times the yardage. The studio checks capacity against the fish: 120 yards for fish to 10 lb, 200 yards from 10 to 25 lb, 300 yards above that.

rig.studio

In the builder every one of these checks runs live against the rest of the rig: the reel's capacity at your line's real diameter, the leader ratio, the sinker bore. Related: the hook size chart, the knot chart for joining braid to a leader, and braid on a rod's line rating. Pick a species above to open it preloaded.

Open the Rig Studio