Cold Plunge Calc

What it does

Cold Plunge Calc gives you a safe, personalized plunge time based on your water temperature, experience, and goal — then builds a free 6-week plan toward the ~11 min/week target from Dr. Søberg's research. Every recommendation links to real studies (Harvard Health, PubMed, Cell Reports Medicine). No sign-up, no tracking, no upsells. Your data never leaves your device. Available in 7 languages. 100% free.

Free cold plunge safety check & time calculator. Get a safe duration based on your water temp and goal, plus a weekly plan. Built on research — not hype.

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