How Thick of a Wetsuit Do I Need?

Wetsuits are one of those things you didn’t think you would need to read online articles to buy correctly. They do not have a single size fits all and are determined by occasion. Continue reading to get all the answers. 

What Are Your Wetsuit Thickness Options?

The thickness of your suit is measured in millimeters, denoted as mm on the suit. Suits usually have the numbers written like 4/3, meaning the thicker parts are 4mm, while the thinner parts are 3mm. The thicker part is around the body to keep it warm, while the thinner is around the sleeves to afford you more flexibility. 

The following are some of the wetsuit thickness options available to you and situations where they are best deployed. 

1 – 2 mm Wetsuits

These suits are the thinnest of the bunch. They are perfect for the summer, offering lightweight protection from ultraviolet radiation and jellyfish. It adds warmth and buoyancy but not so much. The 1 or 2 mm suits are perfect for you to surf, kayak or paddleboard in the summer without compromising flexibility and comfort. 

3/2 mm Wetsuits

The 3/2mm wetsuits are the go-to for the autumn weather and offer lightweight to medium protection from the elements. These suits offer moderate warmth while still offering a lot of flexibility. These suits feature neoprene 3mm thick around the body and 2mm around the limbs. This recipe makes for a durable full suit/steamer suit for surfing, kayaking or paddleboarding

4/3 mm Wetsuits

These suits are 4mm thick around the torso and 3mm thick around your arms and legs. They are perfect for autumn to summer weather and ensure medium to high warmth. 

If you are going surfing or partaking in other watersports like kiting, you will need this wetsuit in temperatures between 9 and 14°C (48 and 58°F). 

Paddleboarders or kayakers might want to stay clear if the temperature is 9°C (48°F) or lower as the thickness of the neoprene layer would negatively influence paddling performance.

5/4/3 mm Wetsuits

This is usually a full suit/steamer suit explicitly designed for the harsh winter weather. It has 5mm thick neoprene around the torso and 4mm and 3mm thick neoprene around the legs and arms, respectively. It offers the wearer a lot of warmth, but the 4mm thick neoprene along the legs might negatively influence mobility. 

5/4/4 mm wetsuits are ideal for general sports like surfing and kiting at 9°C (48°F) or lower. In contrast, kayakers and paddleboarders who need more mobility to paddle should only opt for this wetsuit option when the temperature is 4°C (40°F) or lower.  

6/5/4 mm Wetsuits

This is the warmest wetsuit option and is the go-to in extreme winter conditions. The 6/5/4mm full suit/steamer wetsuit option has 6mm thick neoprene around the torso and 5mm and 4mm neoprene around the legs and arms. This suit would restrict your movement more than the others on this list, and you should only consider it if you will be in the freezing cold. 

Kayakers and paddleboards should stay clear of this wetsuit type as it is too thick and would make paddling relatively tricky. On the other hand, surfers and people partaking in other watersports can use this wetsuit option in the extreme cold. 

What Determines the Thickness of Your Wetsuit?

You should not decide the thickness of your wetsuit in a vacuum, but after factoring in the activity you would be partaking in and the temperature. 

You need to know the activity you would be partaking in before buying or putting on a wetsuit. This is because the activity dictates how much flexibility and mobility you need and how long you will be on the water. 

The following are some on-the-water activities with their corresponding wetsuit thickness options based on the temperature: 

General Watersports, Like Kiting, Surfing

27°C + (80°F + )

In the summer warmth, you do not need thick suits. You can make do with a poly top and rash guard. These offer moderate protection from the sun’s ultraviolet radiation. 

22 to 26°C (72 to 79°F)

You want protection from the elements in moderate warmth without compromising your flexibility. This is where the spring suit comes to its own, as it gives more protection than the rash guard with open elbows and knees for more mobility. 

18 to 21°C (64 to 70°F)

You need a wetsuit that offers lightweight to medium protection from the elements at mildly cold temperatures like these. None suits this description better than the 3/2mm wetsuit. You should opt for one with a flatlock as its no-seal design allows for more flexibility and mobility. 

16 to 17°C (61 to 63°F)

For temperature in this range, you want a 3/2mm neoprene wetsuit. However, you want one with sealed seams rather than a flatlock to keep the heat locked in the suit. 

14 to 15°C (57 to 59°F)

If you were out in temperatures in this range, you would need a wetsuit one layer thicker. The 4/3mm would be perfect as it would lock in more heat while still relatively flexible. Your wetsuit must be sealed to stop the heat from escaping. 

11 to 13°C (52 to 55°F)

You need wetsuits with thicker neoprene layers as you approach more extreme cold conditions. You can make do with the 4/3 mm wetsuits with sealed seams and tape at these temperatures.

9 to 10°C (48 to 50°F)

Kiting or surfing at these temperatures would require medium to heavy protection from the cold. For this reason, you will need the 5/4/3mm sealed wetsuit to lock in the heat and compromise mobility. 

4 to 8°C (39 to 46°F)

This is the most extreme of temperatures, and you will need the most extreme of wetsuits. None fits the description as well as the 6/5/5mm wetsuit. It would give the most warmth of any of the mentioned wetsuits, but you will compromise heavily on mobility. 

Kayaking and Paddleboarding

27°C + (80°F + )

You can make do with a rash guard when kayaking or paddleboarding in the summer. It offers some protection against the sun’s UV rays. 

22 to 26°C (72 to 79°F)

Kayaking or paddleboarding at any temperature in this range would require you to have a neoprene vest. These vests are usually very light on your body and many times sleeveless for added flexibility and mobility. 

16 to 21°C (61 to 70°F)

Slightly colder, and you will need to replace your neoprene vest with a neoprene top. It is only that much thicker, but it will be warmer and offer more protection from the sun. There is little to no compromise on mobility with the neoprene top. 

14 to 15°C (57 to 59°F)

These temperatures are too cold to have only a vest or top on your person. You will need a 3/2mm wetsuit with a flatlock for all the mobility you need on the water. The wetsuit helps you keep and lock the warm in while you are on the water. 

11 to 13°C (52 to 55°F)

There is no change in the thickness of your wetsuit in these conditions. You still have to make do with a 3/2mm wetsuit. The only difference is that you need a sealed suit instead of a flatlock. The seal makes the suit do a better job at keeping the warmth with a little compromise on mobility. 

9 to 10°C (48 to 50°F)

These are icy conditions, but you will have to make do with a 4/3 mm wetsuit. It would be relatively challenging to paddle your kayak or paddleboard with a wetsuit any thicker. You are guaranteed medium to maximum warmth with the suit sealing. 

4 to 8°C (39 to 46°F)

This is the most extreme of conditions, and it calls for the 5/4/3 mm wetsuit. The suit is the thickest option available when kayaking or paddleboarding. Any thicker would jeopardize performance. 


The thickness of your wetsuit is determined by the activity you want to engage in and the air/water temperature. Activities that require you to use your limbs more often should prioritize mobility. However, you can prioritize warmth over mobility in freezing climates.