Enter your water temperature, cold tolerance, and session length. You get a specific thickness recommendation — not a chart that tells you "it depends."
Water conditions
Water Temperature
Quick-pick a surf spot
How do you run temperature-wise?
Session length
Longer sessions drop your core temp — we size up accordingly.
Enter your water temp or pick a surf spot
to see your recommendation.
Wetsuit thickness by water temp
These are baseline recommendations for average cold tolerance and 1–2 hour sessions. Use the calculator above if you run hot or cold, or plan long sessions.
| Water Temp | Recommended Thickness |
|---|---|
| > 72°F / 22°C | Boardshorts or rash guard |
| 68–72°F / 20–22°C | 1–2mm shorty or spring suit |
| 62–68°F / 17–20°C | 2mm full suit |
| 58–62°F / 14–17°C | 3/2mm full suit |
| 52–58°F / 11–14°C | 4/3mm + boots |
| 48–52°F / 9–11°C | 5/4mm + boots + gloves |
| < 48°F / 9°C | 5/4–6/5mm + boots + gloves + hood |
How the calculation works
We start with your water temperature and look it up against a baseline thickness table — the same logic used by most wetsuit brands in their sizing guides, but with two key adjustments most static charts skip.
Cold sensitivity: Cold-sensitive surfers have their effective water temperature shifted 6°F cooler before lookup — meaning 58°F water is treated as 52°F, bumping the recommendation from a 3/2mm to a 4/3mm. Warm-natured surfers get the inverse.
Session length:Sessions over 3 hours drop core temperature meaningfully, even in moderate conditions. Long sessions apply a 6°F effective cooling adjustment. Short sessions (<1 hour) apply a 4°F warming adjustment — your body hasn't cooled down yet.
Frequently asked questions
What wetsuit thickness do I need for 60°F water?
At 60°F (15°C) you need a 3/2mm full suit at minimum. If you run cold or plan a long session, go up to a 4/3mm. 3mm boots are optional but recommended in sustained exposure.
What does 3/2mm mean on a wetsuit?
The two numbers refer to the neoprene thickness in different panels. 3/2mm means 3mm on the core (chest and back) for warmth, and 2mm on the arms and legs for flexibility. Thicker core = warmer. Thinner limbs = easier to paddle.
Does water temperature or air temperature determine wetsuit choice?
Water temperature. Air temperature affects how cold you feel getting in and out, but neoprene insulates against water, not air. Always base your wetsuit choice on water temp. Air temp matters more for choosing a wind-resistant rash guard on top.
How cold is too cold to surf without a wetsuit?
Below 70°F (21°C) most people benefit from at least a thin wetsuit. Below 60°F (15°C), surfing without a wetsuit risks hypothermia within 30–60 minutes. Below 50°F (10°C) you need a full suit, boots, gloves, and hood — no exceptions.
Does session length affect what wetsuit I need?
Yes, significantly. Your core temperature drops over time in cold water. A 1-hour session in 58°F water might be fine in a 3/2mm, but a 3-hour session in the same water warrants a 4/3mm. Our calculator adjusts for this.
Should I size up if I run cold?
Yes — both in thickness and in fit. A wetsuit that flushes cold water constantly is worse than a thicker suit. Make sure the neck, wrists, and ankles seal properly. Our calculator applies a 6°F effective-temp adjustment for cold-sensitive surfers.