PBros
Updated October 3, 2026 · General information, not medical advice.
Time and temperature go together
The colder the water, the shorter most people stay in. Two plunges at different temperatures can feel completely different even at the same number of minutes, so it helps to track both: how long you stayed in, and roughly how cold the water was.
Common water temperatures
- Around 50–59°F (10–15°C): a common range for people new to cold plunging, and for many home tubs without a chiller.
- Around 39–49°F (4–9°C): what many dedicated chillers and ice baths reach. It feels much more intense.
- Open water: temperature changes by season and location. Never go alone, and know how you’ll get out.
A simple pool or aquarium thermometer is the easiest way to know your water temperature.
Common session lengths
Many people start with 30 seconds to 2 minutes and build up slowly over weeks. Sessions in the 1–5 minute range are common for regular plungers; longer sessions are less common and usually in warmer water. The timer is a guide, not a target — get out sooner whenever you need to.
One long plunge or rounds?
Some people do one continuous plunge. Others split the same total time into short rounds, for example 3 × 1 minute with a break out of the water. Rounds can make it easier to build up gradually.
Timing a plunge with PBros
- Open the Plunge tab and set 1 to 15 minutes. It starts at 3.
- Optionally set up to 5 rounds. PBros pauses between rounds so you can get out and reset.
- Start it on your Apple Watch, or leave your iPhone somewhere dry and visible. A Live Activity shows the countdown on your Lock Screen.
- Your sessions are saved to your history, and optionally to Apple Health.
Pairing cold with heat? See the contrast therapy guide.
Time every plunge with PBrosOne-time $4.99 · No subscription · No ads · No account
FAQ
- How long should a beginner cold plunge?
- Many beginners start with 30 seconds to 2 minutes and add time slowly. There’s no single right length, and you should get out any time you feel unwell.
- What temperature is a cold plunge?
- Commonly somewhere between about 39°F and 59°F (4–15°C). Colder water usually means shorter sessions.
- Can I take my phone near the plunge?
- Keep your iPhone dry and away from the water. Use the PBros Apple Watch timer if you want a timer on you.
- Does PBros measure water temperature?
- No. PBros is a timer. It doesn’t measure temperature or recommend a protocol.
- How much is PBros?
- A one-time $4.99, with no subscription, no ads and no account.
Related guides
PBros is a timer and reminder app. It doesn’t diagnose, treat or give medical advice. For adults 18+.
