Please notice: LeaderCalc hasn't been optimized for small screens. Turning some devices horizontally might make it easier to use.


Select the desired specifications for your leader and press "Find leaders" to look up suggestions.

Quick use

Using the form above you can ask LeaderCalc to caculate and show you a number of fly fishing leader formulas meeting your selected criteria. You can read more about the selection tool here.
Leadercalc currently contains 2791 leaders for fly fishing, so there are enough to choose from.

Below you see a couple of randomly selected knotted, tapered leader formulas. Click on the name, category or other elements to see more.

Randomly selected: Bonefish

Category: Saltwater
A simple bonefish leader.
The better you can cast and the less wind, the softer mono you can use giving a more delicate presentation.
Aim for a tippet with at least a 12 lbs breaking strength.

0X - 10.5'
Show all variations

63" of 0.0210
13" of 0.0190 (07X)
13" of 0.0150 (03X)
13" of 0.0130 (01X)
25" of 0.0110 (0X)

Randomly selected: Schweitzer's 4-Segment Perfect Taper

Category: Dry Fly Leaders
Formula designed to tie quickly, turnover with light casts or into wind.
Has a longer tippet than most popper formulas, allowing delicate presentations to finicky panfish.
Ideal for still water fishing.

4X - 7.0'
Show all variations

42" of 0.0200 (08X)
21" of 0.0140 (02X)
11" of 0.0100 (1X)
11" of 0.0070 (4X)


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The GFF money box

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