Square (Reef) Knot

Square Knot, also known as Reef Knot, is used for binding two ropes together. This is one of the first knots all people learn when tying - shoe laces. Unfortunately, this is not a safe knot.


Square knot should not be used when safety is critical due to its tendency to slip, to come undone etc. But, it is suitable knot for many uses, especially if they are not under (heavy) load and when more secure versions can be used.

How to tie Square (Reef) Knot

On the photos below, you can see how this knot is tied. Also, you can click on small photos to see larger gallery.

Take ends of two ropes and cross them (white over blue) to form a half knot. Cross them for a second time (white over blue again) and pull the ends tightly to form the Square (Reef) Knot.

square-knot-extra-half-knotTo increase the safety of this knot, extra half knot is added. Even so, this is still not very secure knot.

Granny Knot

square-knot-grannyIt is very important to take care when crossing the ropes for a second time, since if blue rope is crossed over white, Granny Knot is tied.

Granny knot is considered to be an error. It is very weak knot and it comes undone even more easily than Square (Reef) knot.

Don't use it - plain and simple.

Surgical Knot

square-knot-surgical-1Surgical knot is very similar to Square knot - when making first half knot, cross the ropes twice.
square-knot-surgical-2Make second crossing just like before (white over blue) and pull the ropes tightly to make a knot.

Be sure to know how to make Square/Reef Knot in the hurry and use it when needed - it can be really handy knot to know, just be aware of its shortcomings. When shoe laces come undone, usually no big deal, but to trust someones life to this knot - no way ... :)