Surfboard fins come in a number of different shapes and sizes. Even after familiarizing yourself with how different fin shapes and materials are designed to perform, you’re still left with the question of what size fin to get.
- Fin size should typically correspond with the width of a surfboard’s tail. The wider the tail, the larger the total area of the fins.
- A larger fin will provide more drive and hold.
- A smaller fin will feel looser.
How are Surfboard Fins Measured?
When talking about fin size, we’re either talking about total surface area and/or depth and base length.
You’ll often see single fins classified by their depth, while fin sets are often classified by their overall size based on surface area, base, and depth size.
Generally speaking, smaller surfboard fins will have more turn control while sacrificing drive and hold, while larger fins will have more stability and drive with a larger turning radius. However, as you increase fin size, you also increase drag.
The proper fin size choice boils down to the type of surfboard you’re riding, the type of waves you’re surfing, and the style of surfing you’re hoping to achieve.
Single fins are typically sized by their depth or height. You’ll find single fins anywhere from 6” to 12” in all different templates.
An common starting point for single fin surfboards is to select a fin size that mirrors the length of your board and size up or down from there depending on the dimensions of the board and the type of ride you’re looking for. An 8’ board with an 8” fin, a 10’ board with a 10” fin.
Longboards with a 2+1 setup will require a smaller center fin. These setups typically take the entire fin area (center + sidebites) into account.
For shortboard fins – especially those made by the major fin manufacturers – you’ll see size recommendations based on the surfer’s weight.
Those size guidelines are as follows.
FCS Fins Size Chart:
- XS: under 120 lbs / under 55 kg
- S: 120-155 lbs / 55-70 kg
- M: 145-175 lbs / 65-80 kg
- L: 165-200 lbs / 75-90 kg
- XL: 190+ lbs / 85+ kg
Futures Fins Size Chart:
- XS: 75-115 lbs / 34-52 kg
- S: 105-155 lbs / 48-70 kg
- M: 145-195 lbs / 65-88 kg
- L: 180+ lbs / 80+ kg
A surfer’s weight in these fin guides are really serving as proxies for board size. A smaller surfer is likely going to be on a surfboard with smaller measurements and will require less fins.
It may sound intuitive, but you should really be considering your board when selecting fins.
A board with a wider tail section will work well with more fin, while a board with a narrow tail section may need less fin. A fin cluster that’s closely packed towards the center may require less fin, while a spread out fin cluster may need a larger fin.
Depending on the conditions you’re surfing and the type of surfing you do, you may find a completely random fin set up works best for you. The above should serve as a good starting point to help guide you in your search for more fins. Again, the best advice is to try different setups and experiment.