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: Orvis Delicate

Category: Name-Specific Formulas

5X - 12.0'
Show all variations

36" of 0.0210
24" of 0.0190 (07X)
16" of 0.0170 (05X)
12" of 0.0150 (03X)
7" of 0.0130 (01X)
7" of 0.0110 (0X)
7" of 0.0090 (2X)
7" of 0.0080 (3X)
28" of 0.0060 (5X)

Randomly selected: Orvis Std. Lite-Butt for 3-5 weight lines

Category: Name-Specific Formulas

4X - 8.0'
Show all variations

32" of 0.0190 (07X)
14" of 0.0170 (05X)
11" of 0.0150 (03X)
5" of 0.0130 (01X)
5" of 0.0110 (0X)
5" of 0.0090 (2X)
23" of 0.0070 (4X)


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