Fishing tool
Fishing Line Selector
Mono, fluorocarbon or braid, what pound test to buy, and whether this setup needs a leader — with the trade-offs explained plainly.
How this tool works
Your answers are matched against a rules table built from published tackle guidance and manufacturer specifications, then adjusted for water type, bait and experience level. A small set of hand-written rules covers the combinations where that arithmetic would give a poor answer.
The same rules produce every recommendation on this site, so a species page and this tool can never disagree. Nothing is generated on the fly by a language model, and nothing is influenced by a product. Read the methodology.
- Pound test is not diameterBraid is roughly a third the diameter of mono at the same pound test. Comparing the numbers on two spools tells you very little on its own.
- Cover sets the strength, not the fishMost break-offs happen against wood, rock, shell or grass. Open water lets you fish lighter than the same species in timber.
- A leader is not always neededWe only recommend one when it earns its knot: visibility, abrasion, or teeth.
Line diameter chart
Prefer to read the numbers yourself? The full chart covers every size with what each one is used for.
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Open toolRelated guides
- Fishing Hook Size ChartEvery size from #28 to 12/0 with what each one is used for, and why the same number differs between brands.
- Fishing Reel Size ChartSpinning, baitcasting, conventional and fly reel classes with typical line capacity and what each size is for.
- Fishing Line Size ChartPound test against typical diameter for mono, fluorocarbon and braid, and how to compare them fairly.
- Fishing Rod Size GuideWhat length, power and action each control, and how to read the specs printed on a blank.
Hook sizes by species
- Hook size for bass
- Hook size for trout
- Hook size for crappie
- Hook size for surf fishing
- All species guidesWhere each fish holds, how it feeds, and setups by technique.