A watch can say “50 metres water resistant” and still warn against scuba diving. Another might advertise IP68 yet make no promise about swimming laps. Those labels measure different kinds of protection. Understanding smartwatch water resistance ratings means looking beyond the biggest number on the box and checking what the manufacturer actually approves.
The practical question is whether your watch can survive the water exposure you have planned. Rain, handwashing, pool workouts and fast-moving water create different demands.
ATM and IP ratings measure different things
What a smartwatch ATM rating tells you
ATM stands for atmospheres, a unit of pressure. A 5 ATM watch has been tested against pressure equivalent to roughly 50 metres of still water under specified conditions. That figure is a pressure reference, not an instruction to take the device 50 metres underwater.
Manufacturers often use testing based on ISO 22810. Laboratory conditions are controlled; real activities involve movement, impacts, temperature changes and potentially worn seals. This is why a swimming recommendation matters more than converting ATM into metres.
What a smartwatch IP rating tells you
IP means Ingress Protection. Under IEC 60529, the first digit describes protection against solid particles such as dust, while the second describes water ingress under specific tests. IP68 generally means dust-tight protection at level 6 plus water immersion protection at level 8, with immersion conditions set by the manufacturer.
An X, as in IPX7, means no solid-particle rating is specified in that code. It does not prove the watch lacks dust protection. Nor does a high immersion rating necessarily mean resistance to powerful water jets: those are different tests.
What common smartwatch water resistance ratings mean
IPX7: brief accidental immersion
IPX7 indicates testing for temporary immersion in water up to one metre for 30 minutes. It can reassure you about accidents, but it is not a general smartwatch swimming rating. Some manufacturers specifically advise against recreational submersion of IPX7 watches despite the laboratory test.
3 ATM: everyday splashes, not a swimming promise
A 3 ATM label represents pressure equivalent to approximately 30 metres of water. It is commonly associated with rain, handwashing and similar everyday exposure. Unless the documentation expressly says otherwise, choose something designed for swimming before entering a pool.
5 ATM: often suitable for ordinary swimming
Many fitness watches carry a 5 ATM rating and are approved for pool swimming or surface-level open-water workouts. Garmin identifies its 5 ATM “Swim” category as suitable for swimming, while Apple rates many standard Apple Watch models to 50 metres under ISO 22810 and permits shallow-water swimming.
Neither example makes a standard 5 ATM watch a diving computer. Check the instructions for your exact model, especially for jumping into water, snorkelling or strong jets.
10 ATM: greater resistance, with limitations
A 10 ATM rating represents pressure equivalent to roughly 100 metres of water. Depending on the model, it may support more demanding water sports. It does not automatically make a watch scuba-safe. Diving needs specific approval, suitable depth limits and, where applicable, compliance with diving-equipment standards.
Why IP68 and 5 ATM are not interchangeable
Imagine comparing two watches. The first lists IP68, with the maker specifying a brief immersion test in freshwater. The second lists 5 ATM and explicitly supports pool-swim tracking. If you swim several times a week, the second has the clearer approval, even though IP68 sounds impressive.
Some watches list both ratings because each confirms a different capability. An IP rating cannot simply be converted into ATM, and neither number alone explains every suitable activity. The most useful specification often says “suitable for swimming” or “avoid swimming.”
For a wider view of activity features, see our smartwatch buying guide and compare workout tracking, fit and battery endurance too.
Match the rating to what you actually do
Rain, sweat and washing your hands
Most modern water-resistant wearables are built for ordinary daily exposure, but check your model’s guidance. Sweat and splashes differ from soaking a watch in detergents. Dry the watch and band when practical, particularly after exercise.
Swimming in a pool or the sea
Choose a model specifically cleared for swimming, preferably with a 5 ATM or stronger rating alongside its activity guidance. Saltwater and pool chemicals leave residue, so follow the manufacturer’s freshwater-rinsing and drying instructions afterward. Some bands are unsuitable for water even when the watch body is rated for it.
Showering, hot tubs and saunas
A shower may seem gentler than a swim, but soap, shampoo, hot water and directed spray create other risks. Apple, for example, warns that soap and certain chemicals can damage water seals over time. Steam rooms and saunas may exceed operating guidance. Removing your watch is usually simpler.
Water skiing, diving and fast-moving water
High-velocity impacts differ from static immersion. A watch approved for laps may not be approved for water skiing or scuba diving. Apple distinguishes standard 50-metre models from Ultra models, which have separate recreational diving capabilities and stated depth limits. Never treat a fitness smartwatch as dive safety equipment unless its maker explicitly supports that use.
How to protect water resistance over time
Water resistance is not permanent. Drops, knocks, repairs, ageing seals and chemical exposure can reduce protection without obvious damage. A watch that survived last summer’s pool sessions may not have the same resistance years later.
Before swimming, consult the model’s care instructions and inspect the case for cracks. Avoid pressing physical buttons underwater unless permitted, rinse and dry as directed after salt or chlorinated water, and never charge the watch while its contacts are wet.
Water Lock or a similar mode prevents unintended screen touches and can clear water from a speaker on supported devices. It does not create a seal or upgrade the waterproof smartwatch meaning of the device’s rating.
For upkeep, read how to clean a smartwatch safely. Regular swimmers can compare best smartwatches for swimming with an emphasis on documented activity support rather than slogans.
Frequently asked questions
Does 5 ATM mean I can dive 50 metres?
No. The 50-metre figure describes pressure equivalence under testing, not a safe recreational dive depth. Follow the model’s stated swimming and diving limits.
Is an IP68 smartwatch safe for swimming?
Not necessarily. IP68 immersion conditions vary by product, and an immersion test is not the same as approval for repeated swimming. Check the manufacturer’s guidance.
Can I wear a water-resistant smartwatch in the shower?
Some brands permit certain water exposure, but soap, steam, hot water and strong spray can be problematic. Follow your model’s instructions; taking it off is sensible.
Does water resistance wear out?
Yes. Seals and protective materials deteriorate with time, impacts and chemicals. A rating describes tested capability, not a lifetime guarantee against water damage.
The simplest rule before getting wet
Read ATM as a pressure rating and IP as a defined ingress test, then check the manufacturer’s activity recommendations. For a rainy commute, basic protection may suffice. For pool workouts, seek explicit swimming approval. For diving or high-speed sports, insist on a model rated for that activity. The label is a starting point; permitted use is what makes it meaningful.