Paddle Board Fins: Everything You Wanted To Know But Were Afraid To Ask

Stand-up paddle board fins come in all shapes and sizes and most of you probably have put little thought into what each size and shape does. So for those of you out there who are my people and wanted to know everything about your board let's dive into the exciting world of paddle board fins.

First things first we have to get the name right. They are fins, not skegs, rudders, "the thing that makes the board go straight". If you ever come across companies that sell complete paddle board packages that include the skeg, or rudder, that will be your first clue that these are not high-quality boards, and the people behind the brand are not paddlers. *cough* Amazon paddle boards *cough*.

Key Highlights

  1. Understanding Fin Terminology: Fins, not skegs or rudders, play a crucial role in the performance of your paddleboard by affecting its direction and stability.
  2. Fin Size Matters: The surface area of your fin influences your board's tracking ability and maneuverability, with larger fins offering better tracking but reduced agility.
  3. Fin Base and Rake: The base length affects tracking, while the rake or sweep of the fin impacts stability and ease of turning.
  4. Dolphin Fin: A versatile fin type ideal for a range of activities from flatwater paddling to yoga, offering a balanced profile for stability and maneuverability.
  5. Pivot Fin: Best suited for racing and touring, offering excellent tracking and stability with a larger size and base but minimal rake.
  6. Keel Fin: Great for shallow waters and rental boards, providing good stability and tracking with a small size, large base, and significant rake.

Paddle Board Fin Shape Basics

The size and shape of your fin will have a great impact on how your paddle boards performance characteristics and you can get dial in exactly how you want your board to feel by selecting the right fins.

Fin Size

Fin size refers to the surface area of the fin. In surfboards this is measured in millimeters squared. Paddle board fins are quite a bit larger and you will usually only find the size of the fin in inches. A larger fin will provide track straighter but will be less maneuverable. And if you had the exact same fin that was shorted you would track less but have great maneuverability.

Fin size is also important depending on how you will be using your board. If you are going to be fishing on a stand up paddle board like the O2 Angler then having a small fin in your quiver will allow you to fish in shallow areas. Likewise if you are yogi on either an inflatable sup or solid board and want to maximize your stability a large fin will be key to making you feel very stable.

Fin Base

Fin base is the measurement at you guessed it the base of the fin. The longer the fin base the better your stand up paddle board will track, and the shorter the base of your fin the easier it will be to turn or pivot your paddle board.


paddle board fins

Fin Rake

Fin rake is the amount of sweep that your fin has. Basically how far back does your fin curve away from the base of your paddle board fin. The more rake you have the more stability and tracking your paddle board will have. The less rake you have your paddle board will be easier to pivot and it will take less effort to turn your board.

Now that we have a basic understanding of parts that make up a fin, we can dive deeper into how the shape of the fin affects how your paddle board feels in the water. The amount of shapes is nearly endless but we will dive into the three most common shapes of paddle board fins and how they will feel on your board. They are the dolphin style (rake fin), pivot fin, and the keel fin.

paddle board fins


Dolphin Fin

The dolphin or the rake fin is by far the most common fin that is found on inflatable paddle boards and hard boards. The dolphin is a great all-around performer that will work for everything from surfing, flat water, touring and specialty paddle boarding like yoga or white water. The majority of fins you will see will be dolphin fins.


The standard dolphin fin on your inflatable board will have a very balanced profile, it will have a large size a medium base, and a moderate rake. The large size will make the board track nice and have a very stable feel. The medium base is a very good compromise between tracking and pivoting, and the moderate rake will again strike a balance between tracking and pivoting. If you like the way a dolphin-style fin feels on your paddle board you can keep this style but change up the size to get a completely different feel to your board. If you choose a shorter size you will have less stability and tracking, but the board will pivot quicker and be less likely to catch on the bottom. Everyone should have a dolphin-style fin in their fin quiver and as your skill levels grow you can add different styles of fins and sizes to your quiver.

Pivot Fin

The pivot style fin is mostly found on displacement hull paddle board but is not uncommon to be found on planing hull boards. Regardless of your paddle board style a pivot fin is a great choice if you are sup racing, touring or you just want a fin that tracks well.

Pivot Fins typically have a larger fin size, large base, and very little rake. The large size will make the fin track well and give a lot of stability. The large base will also help the fin track well and give stability. And then the lack of rack will help the pin pivot very quickly. Pivot fins are typically found on boards that have a longer board length. Most of these are touring or race boards with a displacement hull and are boards with high board volume. These boards are made to go straight and go fast over long-distance paddling. A pivot fin compliments these types of stand-up paddle boards very well as the fin shape will help to keep the board going straight and without having to have corrective strokes from the paddler. The down side they do not turn all that great, they do great when you are doing pivot turns but are more of a struggle to make a sharp turn without using a pivot turn.

The pivot fin is a great fin when you want a more stable feel that can improve efficiency over long distances and allow you to achieve faster speeds.

 Paddle Board Pivot Turn

Keel Fin

The keel fin is great for paddling in shallow water and wanting a fin that will still give you great stability and tracking. The keel fin has a small size, large base, and a ton of rake. This combination gives you a fin that tracks very well, gives a lot of stability but sacrifices turning.

A keel fin makes a great fin for use on rental boards as you will have people of all skill levels renting boards, and they typically will forget they even have a fin on the board so when they are coming in to get off the board there is less chance of them dragging the fin on the bottom of the lake or river. They are also a very stable fin so you can have the entire family using the board and having good success standing up while using a smaller fin.

Keel fins are also a good choice when you have limited storage space as you can leave the fin on the board and stack other boards with the fin still in place. A keel fin will also make a shorter board feel like longer boards.



Thank you for attending my Ted talk on stand-up paddle board fins and how a single fin on the right board can make a huge difference in feel. These are the basics to help you get going on your journey to becoming a fin master. As your skill level increases you may want to experiment on how a fin affects your board feel and how the same fin built in a different material feels. Fins are built from everything from flexible rubber to ABS plastic all the way up to high-end carbon fiber. All of these types of materials will change the feeling of the board. So if you have a road trip planned to go surf, or take a yoga trip, white water or any other adventure try some different fins out and experiment.! You will have a great time doing it and will be surprised by how different fins will make your paddle board feel.

And as always if you want more information on our products or want to talk shop hit us up on chat, phone or email!


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