Open any smartwatch listing and you will see “waterproof” near the top; open the spec sheet and you will usually find IP68 or 5ATM instead — two ratings that measure different things. A watch that survives rain can die on its first swim, and the return comes back to you, not the factory.
No consumer smartwatch is truly waterproof
No mainstream smartwatch is waterproof — every one is water resistant to a tested limit. A rating is a pass mark under specific lab conditions: still or moving water, a set depth and time, fresh water, a brand-new watch. Change any of those and the rating stops applying, so never print “waterproof” on its own. Print the exact rating and what it covers. That one habit prevents most of the arguments.
What IP68 actually certifies
IP ratings come from the IEC 60529 standard and cover dust and water in one code. In IP68, the 6 means fully dust-tight and the 8 means protection against continuous immersion in water. The catch is in the detail: the depth and the duration are set by the manufacturer, not by the standard. One maker tests at 1.5 metres for 30 minutes, another at 2 metres for an hour, and both print the same “IP68” on the box.
What the test does not cover matters just as much. IP68 is tested in still, fresh water, with the watch sitting quietly in a tank. It says nothing about the pressure of a swimming stroke, a shower jet, or soapy, salty or chlorinated water. A watch with IP68 alone handles rain, handwashing and an accidental dunk — but it is not a swimming rating, and most makers who print only IP68 do not recommend swimming with the watch.
What 5ATM actually certifies
ATM ratings come from watchmaking (ISO 22810) and measure pressure, not just immersion. 5ATM means the case can hold up against pressure equal to 50 metres of still water. That sounds like a depth limit, but it is not — nobody should take a 5ATM watch anywhere near 50 metres down. The number is a pressure rating, and the test assumes movement, which is why 5ATM is the practical baseline for swimming.
The scale runs like this:
- 3ATM (30m): rain and splashes only. Not for swimming.
- 5ATM (50m): pool swimming, showering, surface snorkelling. Not diving.
- 10ATM (100m): swimming plus water sports such as surfing and jet skiing. Still not scuba diving.
Two points buyers get wrong: the “50 metres” is static lab pressure — a stroke or a jump into a pool creates short bursts well above it — and the rating applies to a new watch, since seals age.
IP68 vs 5ATM side by side
| Rating | What it tests | Safe for | Not safe for |
|---|---|---|---|
| IP67 | Still water, 1 metre, 30 minutes | Rain, spills, a drop in the sink | Swimming, showers |
| IP68 alone | Still water beyond 1 metre, depth and time set by the maker | Handwashing, rain, brief dunks | Swimming laps, hot showers, diving |
| 3ATM | Static pressure, 30 metres | Rain, splashes | Swimming |
| 5ATM | Sustained pressure, 50 metres | Swimming, showering, surface snorkelling | Diving, high-speed water sports |
| 10ATM | Sustained pressure, 100 metres | Swimming, water sports, snorkelling | Scuba diving |
The practical rule: if your customers will swim, buy 5ATM; if the spec sheet shows IP68 with no ATM figure, treat the watch as splash-safe.
The things that kill water resistance
A rating is a snapshot of a new watch on the day it passed the test. Four things wear it down in real life, and your customers will meet all of them:
- Heat. Hot showers, saunas and hot tubs soften the rubber gaskets that keep water out. Heat is the fastest way to kill a rating, at every rating level.
- Soap, shampoo and salt. Soapy water and seawater get past seals more easily than fresh water, and salt and chlorine leave residue behind. Rinse in fresh water and dry the watch after any swim in the sea or a chlorinated pool.
- Buttons pressed underwater. Pressing a button or turning a crown underwater opens a path past the seal for a split second — how most “it was fine until I pressed the button” failures happen.
- Age and knocks. A dropped watch can crack a seal without visible damage, and two years of heat, soap and small knocks wear any rating down. Ratings do not carry a warranty against time.
Most makers also write water damage out of the warranty, even on rated watches — check the wording before you promise a customer that swimming is covered.
How to verify a rating before you order
Water resistance is one of the easiest specs to print and one of the hardest to check from a desk, so get it in writing:
- Ask which standard the rating was tested to. IP68 should cite IEC 60529 with the depth and duration; an ATM rating should cite ISO 22810. A supplier who cannot name the standard has not run the test.
- Ask for the test report, not the label. The report states the depth, the time and the water temperature. A label states nothing.
- Check the exact model. A rating belongs to one model, not to the brand or the series. A certificate for a different watch in the same range does not count.
- Run your own sample test. A controlled 30-minute pool swim on a sample, followed by a fresh-water rinse and a check of the screen, buttons and charging contacts, tells you more than a certificate. Testing a rating on samples is the same discipline as testing battery claims — see our guide to smartwatch battery life claims vs reality.
- Confirm the warranty wording. Ask in writing whether water damage is covered and under what conditions, then print the same wording on your listing.
If the supplier answers with photos of a watch underwater instead of a test report, you have not verified anything.
What to print on your own listing
Use the exact rating and one plain line about what it covers: “IP68 — rain, handwashing and brief immersion. Not rated for swimming.” or “5ATM — pool swimming and showering. Not for diving.” Say what happens after a swim — rinse in fresh water, dry before charging — and whether water damage is covered by warranty. Buyers who swim will pick the right watch, and nobody returns a watch that did exactly what the listing said.
A watch from our range
The ET570 smartwatch carries an IP68 rating on a 1.96-inch HD display with Bluetooth calling, a 340mAh battery rated at 4–6 days of use and 20+ days standby, and magnetic charging. That IP68 rating covers rain, handwashing and everyday splashes — we sell it as everyday water resistance, not a swimming watch, because the spec sheet backs IP68 and nothing more. You can browse more models in our products range, including the smart wear collection.
Buy the rating your customers’ real use needs, verify it with a report and a sample, and print exactly what it covers. The returns you avoid will pay for the testing many times over.
Related reading: Smartwatch Sourcing Guide — How to Choose a Smartwatch Supplier in China
Can customers swim with an IP68 smartwatch?
Not on the strength of IP68 alone. IP68 is tested in still, fresh water with the watch sitting quietly in a tank, at a depth and duration the maker sets — one maker tests at 1.5 metres for 30 minutes, another at 2 metres for an hour, and both print the same IP68 on the box. It says nothing about the pressure of a swimming stroke, a shower jet, or soapy, salty or chlorinated water. A watch with IP68 alone handles rain, handwashing and an accidental dunk, but it is not a swimming rating. If your customers will swim, buy 5ATM, and print the exact rating and what it covers on your listing.
What does 5ATM mean for a smartwatch?
5ATM means the case holds up against pressure equal to 50 metres of still water, tested to the ISO 22810 watchmaking standard — but it is a pressure rating, not a depth limit, and nobody should take a 5ATM watch anywhere near 50 metres down. Because the test assumes movement, 5ATM is the practical baseline for swimming: pool swimming, showering and surface snorkelling, but not diving. The scale runs 3ATM for rain and splashes only, 5ATM for swimming, and 10ATM for swimming plus water sports such as surfing. Remember the rating applies to a new watch, since seals age and heat, soap and knocks wear any rating down over time.
How do I verify a smartwatch waterproof rating before ordering?
Get the rating in writing, starting with the standard it was tested to: IP68 should cite IEC 60529 with the depth and duration, and an ATM rating should cite ISO 22810. Ask for the test report, not the label — the report states the depth, the time and the water temperature. Check the rating belongs to the exact model you are buying, since a certificate for a different watch in the same range does not count. Run your own sample test with a controlled 30-minute pool swim, then a fresh-water rinse and a check of the screen, buttons and charging contacts. Confirm in writing whether water damage is covered by warranty, since most makers write it out.
If you are comparing waterproof specs across models or want samples tested before ordering, talk to us. We source from Huaqiangbei daily and inspect every batch before it ships. Display specs are another area buyers misread — see our AMOLED vs TFT smartwatch displays guide.
