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: Modified Foolproof

Category: Miscellaneous Leaders

5X - 9.0'
Show all variations

54" of 0.0180 (06X)
11" of 0.0160 (04X)
5" of 0.0140 (02X)
5" of 0.0120 (00X)
5" of 0.0100 (1X)
5" of 0.0080 (3X)
22" of 0.0060 (5X)

Randomly selected: Bob Miller's Formula 1

Category: Name-Specific Formulas
Medium line.
From Fly Fisherman Magazine.

6X - 8.5'
Show all variations

20" of 0.0150 (03X)
18" of 0.0130 (01X)
14" of 0.0110 (0X)
12" of 0.0100 (1X)
11" of 0.0090 (2X)
10" of 0.0080 (3X)
9" of 0.0070 (4X)
6" of 0.0060 (5X)


Since you got this far …

The GFF money box

… I have a small favor to ask.

Long story short

Support the Global FlyFisher through several different channels, including PayPal.

Long story longer

The Global FlyFisher has been online since the mid-90's and has been free to access for everybody since day one – and will stay free for as long as I run it.
But that doesn't mean that it's free to run.
It costs money to drive a large site like this.

See more details about what you can do to help in this blog post.