WhatKnot
Bend. Difficulty 2 of 5.

Square Knot

Also known as the reef knot.

Joins two ropes of equal thickness for light loads. Lays flat against whatever you wrap, which makes it the right knot for parcels, bandages, and bundling firewood.

  • CategoryBend (binding)
  • StrengthLight loads only
  • Time to learn5 minutes
  • Best forBandages, parcels, sail reefing
Reef knot, also called the square knot.
Square knot, also known as the reef. Image: Wikimedia Commons.
When to use it

Tidy, flat, and only for light loads.

Use a square knot to bind a parcel, tie off a bandage, or close a stuff sack. Never use it to join two ropes that will take real load. It can capsize and slip, and that is how the granny knot gets its bad name. For load bearing joins, use a sheet bend.

Step by step

Right over left, then left over right.

Take two equal lengths of cord. Hold one end of each in each hand. The mantra you must memorise is right over left, then left over right. Reverse either step and you have a granny knot, which slips and is dangerous.

  1. Hold the two ropes parallel

    Keep both working ends pointing inward. Equal lengths in your hands so the finished knot is balanced.

    If you are joining a known weak rope to a strong one, keep the weaker end on the outside of the finished knot.

  2. Cross right over left

    Take the right hand end and cross it over the top of the left hand end so they form an X.

    Notice which end is on top. That ordering is what you reverse in step four.

  3. Tuck the right end under and up

    Pass the now lower end under the other and back up through the gap. You have just tied the first half knot. Pull both ends gently to keep it flat.

    Resist the urge to fully tighten. You need slack to make the second half.

  4. Now cross left over right

    The end that was on the right is now on the left, and vice versa. Cross the new left over the new right. This reversal is the difference between a square and a granny.

    Memorable rhyme: right over left, left over right makes a knot both tidy and tight.

  5. Tuck and dress

    Pass the upper end under the other and back through. Pull all four strands evenly. The knot lies flat with both standing lines exiting the same side.

    If a standing line and a working end exit the same side, that is the grip pattern of a square. If they cross diagonally, you have tied a granny.

  6. Set, then add stoppers if needed

    Pull all four strands firmly. For light bandages, that is enough. For bundling firewood or tarp corners, add a small overhand in each working end as a backup.

    Never use a square knot to hold a serious load that swings, lifts, or pulses. It can capsize and slip in seconds.

Field check. Run a finger along the knot. Both standing lines should exit on the top side and both working ends should exit on the bottom side, with each pair touching. That is the diagnostic shape of a true square knot.

Watch for these

Common mistakes

  • Tying a granny knot by repeating the same direction. The knot slips under any load.
  • Using it to join two ropes for towing or hauling. It is not a bend for serious loads.
  • Tying it on slippery synthetic line without a stopper knot in each tail.
When you are done

How to untie

Push the standing lines toward each other. The knot capsizes into a pair of half hitches and falls apart. This is also why it is unsafe under load.

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