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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 this new 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: Napoli trout leader

Category: Name-Specific Formulas
Trout Fly leader designed by John Napoli, American Casting Association

3X - 9.5'
Show all variations

48" of 0.0260
24" of 0.0190 (07X)
13" of 0.0170 (05X)
8" of 0.0150 (03X)
3" of 0.0130 (01X)
18" of 0.0080 (3X)

Randomly selected: Medium Line Short

Category: Miscellaneous Leaders
Short leader for medium weight lines in the 4-7 weight classes.

1X - 7.0'
Show all variations

11" of 0.0210
11" of 0.0190 (07X)
15" of 0.0170 (05X)
13" of 0.0150 (03X)
8" of 0.0130 (01X)
8" of 0.0110 (0X)
17" of 0.0100 (1X)

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The GFF money box
The GFF money box
Martin Joergensen

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