How Long Should a Cold Shower Be? A Science-Backed Guide30 seconds of cold water produces measurable benefits. Here's how to build up from 30 seconds to 2+ minutes, what's happening in your body, and the best time of day.Frequently asked questionsIs TimerRush free?Completely free — no account required.Where can I try the timers mentioned in this guide?All timers are at timerrush.com. Bookmark /t/25m or /t/5m for quick one-click access.