Which knot retains 80% to 85% of rope strength?

The figure-eight knot is recognized for retaining 80% to 85% of the rope's strength due to its design and the way it distributes load and stress across the rope fibers. This knot creates a secure loop that is easy to tie and untie, even after heavy loading, which is essential in rescue scenarios.

When tied correctly, the figure-eight knot maintains a strong grip and minimizes the risk of slippage, making it a reliable choice when safety is critical. This characteristic makes it particularly popular among climbers and rescuers who demand strength and reliability from their knots.

In contrast, while other knots like the bowline and butterfly knot have their specific uses and strengths, they do not consistently retain as much strength as the figure-eight. The bowline, for example, is easy to untie after loading but may not hold as securely under all conditions. The butterfly knot is excellent for creating a midpoint anchor but does not have the same strength retention as the figure-eight. The Prusik knot, while effective for certain applications like ascending and descending, also does not maintain the same percentage of rope strength as the figure-eight.