Tippet Size Calculator
Match tippet size, diameter and typical breaking strength to the fly you are about to tie on.
Open tool : Tippet Size CalculatorLeader Formula Builder
Build a hand tied leader formula section by section using the 60/20/20 method.
How to use it
- Pick a total lengthNine feet is the standard trout leader. Go longer for flat clear water, shorter for brush and wind.
- Pick a butt diameterThe butt should be stiff enough to carry the energy of the line. Most trout leaders start around 0.021 inch.
- Pick a tippetUse the fly you plan to fish. The builder steps the midsection down to meet it.
- Cut, tie and testBlood knots or surgeon knots at each join. Pull test every knot before it goes near a fish.
The 60 / 20 / 20 method
The formula splits the leader by proportion rather than by fixed lengths: roughly sixty percent butt, twenty percent stepped midsection, twenty percent tippet. Because it is proportional, the same recipe scales from a seven and a half foot leader to a fifteen foot one without falling apart.
The butt does the work of transferring energy from the fly line. The midsection steps the diameter down in stages so the taper stays continuous. The tippet is the part you keep cutting off and replacing, which is why it gets its own fifth of the length.
This is a starting recipe, not a rule. Casters with a fast stroke often shorten the butt. Anglers throwing heavy flies often stiffen it. Build one, fish it, and adjust the proportions to your own casting.
Common questions
What is the 60 20 20 leader formula
A widely used hand tied recipe: roughly sixty percent of the total length in a stiff butt section, twenty percent in a stepped down midsection, and twenty percent in tippet. It is a proportional starting point that anglers adjust to their casting stroke and conditions.
Why tie my own leaders
Cost, control and repeatability. A hand tied leader can be rebuilt at the vise or on the water for a fraction of the price of a knotless leader, and you can tune the taper to the way you cast.
What knots hold the sections together
Blood knots and surgeon knots are the two most common joins for hand tied leaders. Which one you use is a matter of preference and diameter difference. Test every knot before you fish it.