When you reach the end of your rope, tie a knot in it and hang on. - Thomas Jefferson

Knots weaken the rope in which they are made. When knotted rope is strained to its breaking point, it almost always fails at the knot or close to it, unless it is defective or damaged elsewhere. The bending, crushing, and chafing forces that hold a knot in place also unevenly stress rope fibers and ultimately lead to a reduction in strength

Even if the rope does not break, a knot may still fail to hold. The main ways knots fail to hold are:


The load creates tension that pulls the rope back through the knot in the direction of the load. If this continues far enough, the working end passes into the knot and the knot unravels and fails. This behavior can worsen when the knot is repeatedly strained and let slack, dragged over rough terrain, or repeatedly struck against hard objects.
Even with secure knots, slippage may occur when the knot is first put under real tension. This can be mitigated by leaving plenty of rope at the working end outside of the knot, and by dressing the knot cleanly and tightening it as much as possible before loading. The use of a stopper knot or a backup knot can prevent the working end from passing through the knot. If a knot is observed to slip, it is preferable to use a more secure knot.


Spilling a knot refers to changing a knot's form and rearranging its parts, usually by pulling on specific ends in certain ways. When used incorrectly, some knots tend to capsize easily. Often the capsized form of the knot offers little resistance to slipping or unraveling. A Reef Knot, when misused as a bend, can capsize dangerously.


In knots that are meant to grip other objects, failure can be defined as the knot moving relative to the gripped object. For instance, a simple Rolling Hitch tied around a railing and pulled parallel to the railing might hold up to a certain tension, then start sliding. Sometimes this problem can be corrected by working-up the knot tighter before subjecting it to load, but usually the problem requires either a knot with more wraps or a rope of different diameter or material.


Bight - Any curved section, slack part, or loop between the ends of a rope, string, or yarn

Loop - A full circle formed by passing the working end over itself.

Elbow - Two crossing points created by an extra twist in a loop.

Standing End - The standing end is the longer end of the rope not involved in the knot. It is often (but not always) the end of the rope under load after the knot is complete.

Working End - The active end of a line used in making the knot. May also be called the 'running end', 'live end', or 'tag end'.

Types of Knots