How to Pick an Anchor Rope Size, Type, Length and More

How to Pick an Anchor Rope Size, Type, Length and More

Every anchor needs to be attached to the boat some how. In this article we'll discuss everything anyone ever needed to know about anchor rode.

Video: Everything You Need to Know About Anchor Rode

The video below answers many of the topics addressed here although the article goes into more detail (so there is some reward for reading!).

What is anchor rode?

Rode simply refers to the line and/or chain that connects the anchor to your boat. (Believe it or not, rode is not a typo!)

Ideally, the rode for any anchor setup should consist of both chain and rope. The chain should be on the end with the anchor. Why use both chain and rope? First, it keeps the nylon rode from wearing away by rubbing on the bottom of the sea-floor as the boat swings. Second, because the chain is heavy, it holds the rode to the bottom so the pull on the anchor is horizontal, which reduces the chances of your anchor unsetting.

What type of rope should I use? Nylon, Polyester, or ...?

For most boaters, the best type of rope to use when anchoring is nylon. Nylon has many advantages for anchoring including:

  • It's elastic therefore offering good shock absorption
  • Light and flexible
  • Good strength
  • The most common anchor rope found in marine stores
  • It sinks

Nylon anchor rope is light, flexible, strong, and provides elasticity, which mitigates peak loads on your anchor and boat. Unfortunately, the very fact that nylon stretches means that it creates heat and will eventually break down and need to be replaced. However, you want a strong rope that will absorb the shock from waves and sink, not float. Nylon fits the bill of all of these things.

What's the difference between braided and twisted rope?

In our experience, for most recreational boaters, the difference between using twisted anchor rope or braided anchor rope comes down to preference and taste. Both make excellent choices for an anchor rope but there are some subtle differences between these two styles of rope.

Braided Rope



  • Less stiff and more flexible
  • Frequently stronger than twisted rope
  • Easier on the hands


  • Difficult to splice
  • Less stretch than twisted rope

Twisted Rope



  • Fairly easy to splice
  • Generally less expensive
  • Has more stretch than braided


  • Has a tendency to kink or hockle
  • More stiff and less flexible

How much anchor rope do I need and what size?

One of the questions we get asked most often is, "How much anchor rope and/or chain do I need?" When selecting how much rope and chain you need there are a couple of rules of thumb to use.

Rules for calculating how much and how big of anchor rope to use

  1. You should have 8 feet of rope for every 1 foot of water you will be anchoring in
  2. Your rope should have 1/8" of rope diameter for every 9' of boat.

So this means a 28' boat would want at least a 3/8" or 1/2" diameter rope. Rope is one of those things, like anchors, where bigger normally is better.

As for a rope choice, Nylon is the clear favorite due to the fact it is elastic and relatively strong,

How much anchor chain do I need and what size?

Rules for choosing anchor chain length and size

Along with the rope, you should also have a smaller amount of chain between the rope and the anchor. This chain will keep your rope from rubbing against the seabed and also creates the optimal angle between your rode and the seabed. The general rule of thumb is that you want approximately 1' of chain for every 1' of boat. So a 30' boat would want 30' of chain. However, often certain constraints such as weight and locker room will not allow this ideal chain amount so in these situations you should have at least 10-15' of anchor chain for the reasons mentioned above. For boaters anchoring in extreme conditions and/or for extended periods of time, you will want about 1 foot of chain for every 6 feet of rope. The reason for the different requirements is that, in theory, by having 1 foot of chain for every 6 feet of rope, an optimal angle between the rode and the seabed will be achieved.

 What type of chain do I need? (I am not using a windlass)

If you're not using an anchor windlass, your life is easy! Any chain that you can buy at a marine store that follows the size rules above should be adequate. Hardware store chain can also sometimes suffice but you should always be conscious of the breaking strength of it and ensure that it is galvanized. If you are not using a windlass, you can simply attach your rope to your anchor using a shackle in between (ideally your rope will have an eye and/or thimble spliced into one end to make attaching a shackle easy.

What type of chain do I need? (I am using a windlass)

Thinking about using a shackle with your windlass? Don't do it!

If you are using an anchor windlass then your choices are limited and you must use only the type and size of chain specified by the windlass manufacturer. Normally this type of chain will be G4 or BBB chain. Don't have your windlass manual? We have an article that lists the type and size of chain required by most popular sizes of windlass here. Windlass chain is a whole other topic and in fact, we have another article all about windlass chain here. If you are using a windlass, remember that you must splice your rope to your chain as a shackle going through your windlass gypsy will be bad news. (You can also hook the shackle around your windlass as well once it gets to that point but that's a pain!) You can purchase a prespliced rope and chain package or you can splice your own.


Recent Posts

Boating Vocabulary: Words Boaters Should Know
Boating Vocabulary: Words Boaters Should Know
Boating has a long history and has played, and still does play, a crucial role in exploration, transport, and recreation. With that kind of legacy comes a vast vocabulary developed to help people work and play in the marine environment. While there are entire dictionaries dedicated to boating terminology, here we will highlight some of the most important and common that most modern boaters should know.
Prevent Dock Line Chafing and Know When to Replace Failing Boat Lines
Prevent Dock Line Chafing and Know When to Replace Failing Boat Lines
Line chafe is one of the biggest enemies when it comes to boat ownership. Chafed and weakened boat lines are not only dangerous for overhead rigging but can also cause dock lines to fail and send your expensive investment adrift. It's important to know how to prevent dock line chafe and to recognize when damaged dock lines are in need of replacing.'s Anchoring Quiz's Anchoring Quiz
Test your anchoring knowledge with our anchoring quiz!
Boat Ramp Etiquette: The Do's and Don'ts for a Swift Boat Launch
Boat Ramp Etiquette: The Do's and Don'ts for a Swift Boat Launch
During peak boating season the ramps are crowded and people are anxious to get on the water. If you're an avid boater, chances are you've seen tempers flare between fellow boaters competing for a spot on the boat ramp. Spare yourself and others the unnecessary frustrations at the boat ramp by following these simple ramp etiquette do's and don'ts.
How to Repair or Patch a Hole or Tear in a Boat Cover
How to Repair or Patch a Hole or Tear in a Boat Cover
Before you run out and drop a bundle on a brand-new cover, consider repairing your existing cover with a patch. It will be less expensive than a new cover, will not take up too much time, and will be more environmentally friendly than sending a cover to the landfill. In this article we’ll discuss the materials and steps required for a basic DIY boat cover tear or hole repair.
How to Launch a Boat by Yourself
How to Launch a Boat by Yourself
Launching a boat can be one of the most difficult and stressful aspects of boating. This stress only gets worse if you're launching a boat without any other helpers. If you're not careful about your planning and execution, your day can take a turn for the worse in a matter of seconds. Luckily we've assembled the tips and tricks to start your day off right and to avoid doing any unnecessary harm to your boat or vehicle.
The 5 Best Tips for Preventing Mold and Mildew on Your Boat
The 5 Best Tips for Preventing Mold and Mildew on Your Boat
Once mold and mildew get established, they are difficult to get rid of, and most boat insurance does not cover related damage. The key to dealing with mold and mildew is to prevent them by creating conditions adverse to their development. We've collected the five best tips to prevent mold and mildew on your boat.
Boat Cover Types and Materials
Boat Cover Types and Materials
Choosing a cover can be confusing given the number of different materials and the different variations of covers. We’ll cover some of the basics that you’re going to see out there.
Retrieve a Fouled Anchor and Tips to Prevent Snags in the First Place
Retrieve a Fouled Anchor and Tips to Prevent Snags in the First Place
It happens far too often. You're ready to pull anchor and set off after a relaxing float only to find that your anchor won't budge. Don't reach for that knife just yet, there are several retrieval methods you can use to salvage your anchor as well as your trip. Here a few tips to retrieve a fouled anchor.
How to Deploy and Use a Sea Anchor or Drogue
How to Deploy and Use a Sea Anchor or Drogue
Sea Anchor, Storm Drogue, Sea Brake, Parachute Anchor, Drift Sock: these are several names used to describe devices deployed to create drag on a vessel in open water. No matter how many different monikers you find out there, they are referring to one of two types, 1) a parachute or cone shaped piece of fabric dragged from the bow (most accurately called a Sea Anchor), or 2) a fabric cone or series of cones dragged from the stern (most accurately called a Drogue). In this article we’ll look at the differences between the two, their uses, and how to deploy and retrieve them.