Average Weight of Sailboat Keels (5 Most Common Types)

On this page:

1. How Much Does a Sailboat Keel Weigh?
2. Does Keel Material Matter?
3. How Do Sailboat Keels Work?

How Much Does a Sailboat Keel Weigh?

There are three ways to explore sailboat keel weight:

1. based on sailboat size
2. based on keel design
3. based on popular sailboats

Below, I'll list the average keel weight based on all three factors, starting with sailboat size.

Keel weight based on sailboat length

Size	Average length	Average weight	Average keel weight
Small sailboats	15 to 20 feet	400-2,500 pounds	160-1000 lbs
Medium sailboats	21 to 25 feet	2,500-5,000 pounds	1000-2000 lbs
Cruising sailboats	27 to 32 feet	7,000-12,000 pounds	2800-4800 lbs
Large sailboats	35 to 40 feet	12,000-30,000 pounds	4800-12000 lbs

However, the total required weight is not just determined by sailboat weight, but also by sail area and the length of the keel.

Keel weight based on keel design

Since the amount of ballast is very dependent on the boat length and indented sailing conditions, we have to make a lot of assumptions to pair each keel design to an average weight, making it an impractical comparison.

The difference in average keel design weights is mostly based on different standard applications of these keel designs. However, it is possible to show the effects of keel design on ballast weight requirements, by comparing the same class of boats with different keel designs.

Keel design weight differences

The examples below are the average keel weights on similar 40-foot cruising sailboats, using different keel designs, allowing for a comparison in ballast requirements based on design alone:

• Full keel: 8,000 lbs
• Bulb keel: 6,000 lbs
• Fin keel: 5,000 lbs
• Wing keel: 5,000 lbs

As you can see, the deeper the keel runs, the lower the required ballast will be. Bulb keels look like fin keels but are shorter, using more ballast to enable a shorter design.

Full keels and modified full keels run less deep, thus requiring more ballast to provide the same righting moment. Fin keels and wing keels run the deepest, reducing the amount of ballast needed.

Leeboards are unweighted, as are daggerboards most of the time. Centerboards can either carry ballast or not, based on the sailboat model.

Keel designs from heavy to light

We can also compare keel design weights based on their expected relative weight. So let's say we have a sailboat and we just switch out the keel, how heavy would each keel be relative to the others? From heaviest to lightest:

1. Modified full keel
2. Full keel
3. Bilge keel
4. Bulb keel
5. Fin keel
6. Wing keel
7. Centerboards
8. Daggerboards
9. Leeboards

Keel weights of popular sailboat models

Boat model	Displacement	Keel Design	Ballast in pounds
Jeanneau S.O. 409	16,424	Wing keel	4,982 lbs
Bavaria Cruiser 40	19,139	Wing keel	6,131 lbs
Beneteau Oceanis 41	18,624	Fin keel	5,071 lbs
Hanse 415	19,621	Bulb keel	6,395 lbs
Catalina 385	15,500	Fin keel	5,200 lbs
Hunter 39	18,501	Fin keel	6,027 lbs
1956 Bounty II	18,800	Full keel	8,000 lbs

• Source: How Sailboats Measure Up, October 16, 2012, Jeremy McGeary, Cruising World

Using the ballast to displacement ratio

The ratio used to describe the weight of the keel compared to the total weight of the sailboat is called the ballast to displacement ratio. You can use this ratio to get a general idea of the properties of a boat, but it does have major shortcomings.

For an overview of how to use the ballast to displacement ratio, I recommend reading my article on it.

Does Keel Material Matter?

While keels can be made out of several materials, it shouldn't affect the amount of weight you use. The ballast should be equal either way. Keel materials depend mostly on available space and budget. If you have restrictions on space, you need a heavier material to get the same amount of ballast. If you have restrictions on budget, you typically use something lighter. Having restrictions can be somewhat of a double bind.

How Do Sailboat Keels Work?

In short, a sailboat keel's weight is used to to increase displacement and lower the center of gravity, while its surface is used to increase wetted surface. This helps to stabilize the boat, but also provides directional stability. For a more detailed explanation on how sailboat keels work, I recommend reading this article.