Pulse Plunge Sensor
A compact Bluetooth temperature sensor plus the Yutori app. Drop it into your existing cold tub or mount it just below the waterline and get accurate water temperature, automatic session logging, and Live Coach guidance — no chiller or hardware changes required.
Ships directly · No subscription required
Compatibility
Works with any cold plunge.
If it holds water and you can reach it with your phone, Pulse Plunge Sensor can instrument it.
Stock tanks & chest freezers
Galvanized, plastic, or converted chest-freezer tubs. Any DIY cold plunge setup.
Purpose-built plunges
Commercial cold plunge systems from any brand. The sensor simply sits in the water.
Indoor or outdoor
IP68 submersible enclosure handles cold water and splashes easily. −40 to 85 °C operating range.
The Yutori App
Know exactly how cold you’re training.
The sensor gives you the number. The app gives you the context, coaching, and safety layer.
Live Water Temperature
Real-time water temperature displayed on your phone. Clear indication of your usual training range vs today’s actual temperature — so “45 °F plunge” is a number, not a guess.
Automatic Logging
Every plunge is logged with duration, start/end water temperature, temperature curve, peak heart rate, and HRV change. Written into Apple Health as a workout.
Live Coach for Cold
Estimates a safe time window using your history, current water temp zone, and demographics. Monitors HR ceiling, dangerous cold zones, and max durations.
Contrast Session Tracking
Used with a sauna sensor, it tracks alternating hot and cold as a single practice. Live Coach adjusts commentary for where you are in the hot–cold cycle.
Safety Net for Cold
Customizable session timers and prompts (“take your hands out,” “time to come up”). Emergency contacts stored on your device. If a plunge appears to go seriously wrong, the app escalates with stronger alerts and notifications.
Depends on your phone, sensors, and network. This is a backup layer, not a medical monitor or replacement for supervision.
Cold Adaptation
Watch your relationship with cold change.
Over weeks, the same data becomes a picture of your cold adaptation.
Duration Trends
Average cold plunge duration and typical water temps, tracked over weeks and months.
Cold-Shock HR
Peak heart rate in early vs later sessions. See your autonomic adaptation in real numbers.
Tolerance Tracking
How long you can stay in a given temperature band comfortably, tracked and trended over time.
Pricing
$87, shipped.
One-time purchase. The free tier includes live water temperature and basic session history. Premium coaching is optional.
Sensor + App
Hardware sensor, live water temperature, automatic plunge logging, basic session history.
Yutori Premium
HR/HRV integration, Live Coach for cold exposure, long-term trends, AI insights, cold and contrast protocols, and safety workflows.
Premium is $4.97/month or $39.99/year. Sauna + plunge setups can run two sensors under the same account for contrast session tracking.
Specifications
Full specs.
| Product | Yutori Labs: Pulse Plunge Sensor |
| Type | BLE water temperature sensor + Yutori mobile app |
| Measurement | Water temperature (TMP117-class), motion available |
| Temp range | −40 to 85 °C (−40 to 185 °F), typical ±0.1–0.2 °C in 0–25 °C |
| Protection | IP68/IP69K polycarbonate enclosure, submersible |
| Battery | CR2477T coin cell, user-replaceable, ~1–2 years typical |
| Radio | BLE 5.0, ~5–20 m indoor/outdoor range |
| Platforms | iOS; Apple Health integration, others via connectors |
| Placement | Just below the waterline, away from direct chiller inlets |
| Cross-use | Integrates with sauna sensor for contrast session tracking |
Important
Safety & limitations.
Pulse Plunge Sensor and the Yutori app are tools for awareness, not guarantees of safety.
Not a medical device
The sensor and app are not medical devices and do not diagnose, treat, cure, or prevent any disease. They should not replace medical advice or supervision.
Connectivity-dependent alerts
Emergency workflows depend on your phone, sensors, and network. If connectivity is poor, alerts may be delayed or unavailable.
Hypothermia risk
Cold water exposure carries real risk. Never plunge alone without a safety plan. The app’s timers and guardrails are estimates, not substitutes for judgment.
Heed your own limits
If you feel numbness, confusion, or distress, exit the water immediately and seek help — regardless of what the app shows.
Know your cold. Train your cold.
$87, one-time. Pair with the Yutori app for precise temperature, coaching, and safety rails.