What Do Fins Do On a Surfboard?

How do Surfboard Fins Work?

A fin impacts a surfer’s performance in multiple ways, including:

  • Provides more acceleration and overall speed
  • Increase the board’s ability to grip in the water
  • Allows for more hold during turns
  • Reduces backend sliding and decreases the chance of a wipeout

They do this by creating horizontal lift, which is where the backend stability comes from and why the board can remain in control during sharp turns. They also create drag, which impacts the speed of the board.

Different Fin Setups

Different fin setups will include varying types, numbers, and combinations of fin, including:

  • Single: The original fin setup, containing just one large fin. The fin is much larger and wider than normal to provide the control required. Many Longboards have a single fin.
  • Twin Fin: Two smaller fins that provide more speed and easier turning than a single fin.
  • Tri-Fin: Also known as a “Thruster”, the tri-fin has three fins of the same size. This is the most common setup on a surfboard, and it includes two fins sitting semi-parallel to one another, along with a middle fin.
  • 2 + 1: Three fins, with one large and two smaller ones. The two side fins are often removable to provide the surfer with more control when riding smaller waves.
  • Quad Fins: Four fins, two on each side, with the side fins placed in a similar position as the ones on a Thruster setup. Commonly used on Shortboards, this setup can vary considerably and allows for a lot of customization.
  • Diamond Quad: Four fins designed in a way that is said to make turning easier in Longboards. It was conceived by John Coby and was first tested in 2011.
  • Bonzer: A three or five fin setup developed in the 1970s. Bonzer was created by the Campbell brothers in the 1970s and was designed to tackle high waves near their home in California.
  • Tunnel Fun: A tunnel-shaped fin that was first used in the 1960s and continues to be used by modern shapers, often in the creation of Longboards.

Getting the Right Fin

As a beginner, you don’t really need to concern yourself with whether or not a fin is too big or too small, nor do you need to worry about whether you have one, two, or five fins. Just buy a board that is right for your skill level and your weight and you’ll be good to go.

It’s certainly something that pro surfers building custom boards should consider, but as a beginner, just stick with the basics.