Fishing Reel Line Capacity Calculator

Use this free fishing reel line capacity calculator to estimate how much line a reel holds when you change line diameter.

How the fishing reel line capacity calculator works

New capacity = rated capacity × (rated diameter ÷ new diameter)². Thinner line packs more on the spool.

Frequently asked questions

Why does diameter matter?

Capacity depends on the line’s cross-section area, so halving diameter roughly quadruples capacity.

Results are estimates for general information only. They are not a substitute for professional advice where applicable. Found a mistake? Report an error.