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Free tackle planning tool: enter the test rating from your spool as lb (US) or kgf, optionally discount for knot efficiency, and see nominal and effective strength plus common drag-setting ballparks (¼ and ⅓ of effective lb).
Last updated: April 8, 2026
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100% = ignore knot loss; try 70–90% for weaker knots.
Nominal (label)
10 lb · 4.54 kgf
44.5 N
Effective @ 100%
10 lb · 4.54 kgf
44.5 N
Drag setting ballpark (of effective lb)
~25%: 2.5 lb · ~33%: 3.33 lb
Many anglers start near ¼–⅓ of line strength for drag; match reel, technique, and fish.
Nominal rating is from the label; real break strength varies by knot, braid vs mono, age, and nicks. Use drag settings and tackle within your skill and regulations.
Spool rating
Match the box
Pick the unit printed on your line or the one you think in.
Compare specs
N readout
Handy when cross-shopping international products.
Efficiency %
Effective strength
Rough stand-in for palomar vs sloppy knot—tune from experience.
Reel setup
Starting point
Not a max—adjust for species, structure, and rod.
Label vs knot
Two totals
See how much a 85% knot shaves off in pounds.
Real water
Varies
Abrasion, UV, and shock loads change outcomes.
10 lb test, 100% knot, nominal strength
Nominal (N)
44.48 N
~25% drag (lb)
2.5 lb
We treat the number on your spool as a nominal strength rating. If you choose lb test, we convert to kilogram-force and newtons using standard force conversions. If you choose kgf, we convert to lb and newtons. Knot efficiency scales all three consistently. Drag hints multiply effective lb by 0.25 and one-third for quick reel-setup estimates.
1 lbf = 4.4482216152605 N; 1 kgf = 9.80665 Nlb ↔ kgf via 1 kgf ≈ 2.20462262185 lbeffective = nominal × (knot % ÷ 100)More outdoors? Try hiking pack weight and kayak paddle length.
Get a Custom Calculator for Your SiteDrop knot efficiency to 80% to approximate a knot that tests near four-fifths of straight-line strength. Effective pounds, newtons, and suggested drag fractions all scale together.
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