247SportTools
Swimming · Open Water

Open Water Swim Calculator

Estimate your open water swim time adjusted for wetsuit, current and sighting.

Open water estimate

Estimated open water time

Top picks compared

PickProductBest for
Top pick Zone3 Vision Wetsuit Entry-level but high-buoyancy triathlon wetsuit. Significant pace improvement. Check price →
Option Swim Skins (Sleeveless Wetsuit) For warmer races — non-wetsuit legal triathlon alternative. Check price →
Option Tow Float (Open Water Safety) Visible orange float for safety in open water swims. Check price →

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Frequently asked questions

How much does a wetsuit help swimming?

3-10 seconds per 100m for recreational swimmers. The main benefit is buoyancy — legs float higher, reducing drag. Elite swimmers with excellent body position benefit less.

Why is open water slower than pool swimming?

No walls (no tumble turns that add speed), no lane ropes (more turbulence), sighting (raising the head slows momentum), and often colder water. A typical open water add-on is 8-15 seconds per 100m for recreational swimmers.