Is the WHOOP 4.0 fully waterproof?
Rated IP68 with a 10-metre depth claim. Real-world tested across pool laps, ocean swims, daily showers and a couple of hot tubs. The marketing claim is true with one practical caveat.
The official rating
WHOOP 4.0 carries an IP68 rating with a 10-metre depth limit. IP68 means total dust ingress protection (the "6") and "continuous immersion in water beyond 1 metre" (the "8"). The 10-metre figure is WHOOP's specified limit.
In English: showering, swimming, and accidental drops in any normal water environment are fine. Diving below 10 metres or exposing to high-pressure water (jet washes, very deep pools) is outside the rating.
What I tested over six months
- Daily showers with normal soap and shampoo — no issues at all.
- 40+ pool sessions at standard chlorinated indoor pools — no issues. Heart rate continued to log normally underwater.
- 4 ocean swims at UK beaches — no issues during, but I rinsed the band immediately after to wash off salt.
- 2 hot tub sessions at around 38°C — no issues but the strap felt slightly softer afterwards.
- Light rain on hikes — completely irrelevant; the band does not notice.
- Boiling water rinse (accident) — band fine, strap discoloured slightly.
Six months in, the band itself is electronically perfect. The original strap shows the wear pattern of any fabric strap exposed to water and friction — slight fading, slight stretching, but nothing that affects function.
They claim ease and support when you sign up. And they make it sound like you're paying for the subscription and not the hardware. I need to be able to move the wearable depending on what sport I'm doing. And unfortunately whoop is the only one that allows me to do so atm.
Where waterproofing breaks down
The strap, not the band
The waterproof rating covers the WHOOP module — the small bean-shaped sensor that contains all the electronics. The fabric strap is not waterproof in any meaningful sense. It absorbs water, dries slowly, and degrades faster than dry-only use.
WHOOP's strap warranty covers normal degradation; replacement straps are included free with active membership. So this is not a real cost concern, just a practical one — wet straps stay wet for hours, particularly in winter.
Salt residue and sweat
The biggest practical issue with regular water use is build-up. Salt from sea water, mineral residue from hard tap water, and dried sweat all accumulate around the charging contacts on the underside of the module. Over months this can:
- Make the slide-on battery pack sit unevenly.
- Leave brown stains on the strap.
- Cause skin irritation under the band.
Solution: every couple of weeks, take the band out of its strap, rinse the module under fresh water for 30 seconds, dry with a soft cloth. Five-minute job, prevents the issues.
Heat
Lithium batteries lose capacity faster at high temperatures. Frequent saunas, hot tubs above 40°C, or leaving the band in a hot car will degrade the battery faster than spec. Occasional exposure is fine; daily exposure will halve the band's effective lifespan.
Compared to Oura
Oura Ring carries a 100-metre rating — significantly higher than WHOOP. Practically, both handle every realistic water use case. The difference matters only for actual scuba divers (where Oura is fine and WHOOP is officially out of spec).
If your WHOOP does get water damage
Water damage that occurs within the rated conditions is covered by warranty as a manufacturing defect. WHOOP support requires:
- Photos of the damage.
- The order/membership reference.
- An honest description of what happened.
Replacement bands are typically shipped within 5-10 working days. Water damage outside the ratings (deep diving, jet washing) is not covered.