FISHINGCRITICHow does the line capacity converter work?
It holds spool volume constant and scales line length by the square of the diameter ratio. This is an estimate, not a measured spool fill.
yards new = yards rated ×
(diameter rated / diameter new)²
What reference diameter should you use?
Use the diameter of the actual line behind the rated capacity. If the maker prints only lb/yd, that diameter is unknown. Our catalogue mode offers a labelled Trilene XL reference assumption; replace it with your own measurement when you have one.
Do not replace a braid diameter with a “mono equivalent” strength. Pick the named line series and strength in the tool. Diameters differ between lines with the same pound test.
What limits the estimate?
Line packing, line shape, stretch, backing and spool fill height can change the actual length. The formula assumes round line, equal packing and no backing. Do not treat the result as a drag setting or a line strength recommendation.
Where are the line diameters from?
Trilene XL diameters come from Berkley’s model data in inches; we multiply by exactly 25.4 to use millimetres. InvizX and Smackdown diameters come from Seaguar’s published charts in millimetres. We do not interpolate missing strengths.
Where do these facts come from?
The links identify source URLs and check dates. The source data records access limits.