Double Fisherman's Knot vs Triple Fisherman's Knot
Life-safety notice
TyingPoint's illustrations are for learning. For any life-safety use — climbing, rope access, rescue, or load-bearing rigging — seek qualified in-person instruction, and always inspect and test every knot before you trust your weight (or anyone else's) to it.
| Trait | Double Fisherman's Knot | Triple Fisherman's Knot |
|---|---|---|
| Family | bend | bend |
| Diagram steps | 6 | 6 |
| Life-safety context | Yes | Yes |
| Primary use | join two ropes | join two ropes |
The difference between these two comes down to a single extra wrap per side, and the entire question worth asking before choosing either is whether the specific cord in your hands actually needs it.
Both knots interlock a pair of overhand-family knots pulled snug against each other, and both are built for the same job: a permanent, closed loop of cord that's never meant to come apart again. Where they diverge is friction reserve. On ordinary accessory cord with typical surface texture, two wraps per side already generate more than enough grip to hold at roughly 65-70% retained strength - adding a third wrap there buys almost nothing and just adds bulk and untying difficulty for no real benefit.
That calculation flips on genuinely low-friction material - thin, coated, or high-modulus cord engineered for minimal surface drag as part of its performance profile. There, the double version's margin can run thinner than it would on traditional cord, and the triple fisherman's third wrap exists specifically to restore that margin, nudging retained strength up to roughly 70-80% at the cost of a bulkier, harder-to-untie result.
Where the double version wins
For ordinary accessory cord and standard climbing materials, the double fisherman's knot is the more practical everyday choice - it's faster to tie, less bulky, and its friction margin is already more than adequate on typical cordage.
Where the triple version wins
On genuinely slick modern cordage - certain coated or treated cords, some thin high-strength accessory cord - where the double version's margin feels thin, the extra wrap buys real security at a modest cost in bulk and untying difficulty.
What the extra wrap doesn't fix
Neither variant should be mistaken for a knot you'll casually untie afterward. Both are meant to be permanent joins for cord that's becoming a fixed loop, not a bend you'll be breaking down at the end of the day - if that's what you actually need, a zeppelin bend or similar easier-to-untie bend is the better tool regardless of which fisherman's variant you were considering.
The honest verdict
Default to the double fisherman's knot for ordinary cord - it's the standard for good reason, and the extra step of tying a triple isn't worth the bulk and untying difficulty unless the specific cord in your hands is genuinely slicker than typical accessory cord. Reach for the triple version specifically when you know the cordage is unusually low-friction, not as a habitual upgrade.
How to tell if your cord actually needs the extra wrap
A practical test worth doing before committing to either: tie a double fisherman's knot in the specific cord you're using, dress it fully, and then try to work it loose by hand under moderate tension. If it holds firm and shows no tendency to creep, the double version's margin is adequate for that cord. If it feels like it wants to slip or the wraps seem to be sliding against each other even before real load comes on, that's a genuine sign the cordage is slicker than typical, and the triple fisherman's knot's extra wrap is worth the added bulk and untying difficulty.
Why manufacturers occasionally specify one over the other
Some cord manufacturers and equipment guides explicitly recommend the triple fisherman's knot for specific low-stretch, high-strength cords precisely because those materials are engineered for minimal surface friction as part of their performance profile - the same low-friction coating or fiber treatment that makes the cord perform well under load also makes a standard double fisherman's knot's margin thinner than it would be on more traditional, higher-friction accessory cord. Checking a specific cord's manufacturer guidance, where available, is worth doing rather than guessing purely from general knot-tying advice like this comparison.
Building the habit of checking rather than assuming
The overarching lesson from this whole comparison is that neither the double nor the triple fisherman's knot is universally correct - the right choice depends on the specific cord in hand, and building a habit of actually checking that cord's behavior rather than assuming a default is worth more than memorizing a fixed rule.
Age and UV exposure shift the calculation too
Cord that's aged in storage or seen real sun exposure over a season can lose some of its original surface texture and friction characteristics even without looking obviously damaged, which is one more reason to lean toward the triple fisherman's knot's extra security margin on cord you're not entirely confident is still behaving like new. When in doubt about a specific piece of cord's condition, the modest extra bulk of the triple version is a small price for real peace of mind.