IP vs ATM Ratings for Watches — Complete Guide

1

What Is an IP Rating?

Ingress Protection — the international standard for dust & water resistance in electronics

IP stands for Ingress Protection — an international standard defined by IEC 60529 that classifies exactly how well a device is sealed against solid particles (dust, grit) and liquids (water, sweat). Every IP rating has two digits: the first digit (0–6) measures solid/dust protection, and the second digit (0–9) measures water protection. The higher the number, the stronger the seal.

First Digit — Solid / Dust

6

Dust-tight

Scale: 0 (no protection) → 6 (completely dust-tight). All IP6X watches share complete dust protection — no particles enter under any conditions.

Second Digit — Water / Liquid

5–8

Jet-spray to deep immersion

Scale: 0 (no protection) → 9 (high-temp pressure jets). For watches, you'll typically see 5 (jets), 7 (1 m submersion) or 8 (continuous immersion).

Common IP Ratings on Watches — with examples

IP65

Dust-tight · Low-pressure water jets

Dust-proof, splash-proof and rain-proof — safe for outdoor wear, rain and handwashing, but not for swimming or submersion. The second digit "5" means water projected from a 6.3 mm nozzle at low pressure from any direction.

Basic outdoor trackers Budget sports bands Fashion smartwatches

IP67

Dust-tight · Temporary submersion to 1 m

Dust-proof and splash-proof, plus brief submersion — the "7" means the device survives being submerged up to 1 metre for 30 minutes. Good for accidental drops but not lap swimming.

Fossil Gen 6 Fitbit Charge 6 Mid-range smartwatches

IP68

Dust-tight · Continuous deep immersion

The gold standard for smartwatches — "8" means continuous immersion beyond 1 metre, with depth and duration defined by the manufacturer. Samsung Galaxy Watch specifies 1.5 m; Google Pixel Watch specifies 3 m.

Samsung Galaxy Watch 7 Google Pixel Watch 3 Apple Watch Series 10

IPX8

No dust rating tested · Continuous immersion

Water-only version of IP68 — the "X" means dust resistance was not tested or not claimed. The water protection is identical to IP68. Seen on some older fitness trackers that didn't require dust certification.

Fitbit Charge 3 Garmin Forerunner (older) Older fitness bands

🔬 Governing standard: IEC 60529, published by the International Electrotechnical Commission. Tests are conducted in fresh water at 18–25 °C. Saltwater, chlorine, and chemical exposure are not part of the IP test and must be verified separately.

2

What Is an ATM Rating?

Atmospheres — the traditional watchmaking pressure standard for water resistance

ATM stands for Atmospheres — a pressure-based measurement system used primarily by the traditional watchmaking industry. One ATM equals one atmosphere of pressure, which is approximately the pressure found at 10 metres of water depth. A watch rated 5 ATM can withstand pressure equivalent to 50 metres of static water depth — though in practice this does not mean you should dive to 50 m with it.

1 ATM

= 1 atmosphere

=

10 m

of water depth

=

1 bar

of pressure

So a 5 ATM watch = 50 m equivalent. A 10 ATM watch = 100 m. A 20 ATM watch = 200 m. The higher the ATM number, the more pressure the watch can handle — and the more water activities are safely supported.

Common ATM Ratings on Watches — with examples

3 ATM

30 m equivalent · Splash only

Safe for rain, handwashing, light splashes. Not for swimming. Found on fashion watches and entry-level trackers. E.g. Michael Kors Access Runway, Fossil Gen smartwatches (older).

5 ATM

50 m equivalent · Swimming

Safe for pool and ocean swimming, showering, light water sports. The minimum standard for a swim-ready watch. E.g. Apple Watch Series 11 (WR50), Garmin Vívomove, Samsung Galaxy Watch 7.

10 ATM

100 m equivalent · Water sports

Safe for snorkelling, water skiing, surfing and vigorous swimming. Confident for most active water sports. E.g. Garmin Fenix 8 (10 ATM), Apple Watch Ultra (WR100 = 10 ATM).

20 ATM

200 m equivalent · Scuba diving Highest common

Rated for recreational scuba diving and serious water sports. E.g. Casio G-Shock MTG series, Seiko prospex dive watches, dedicated professional dive watches.

🌊 Key caveat: ATM ratings are tested under static pressure in a lab. Real-world swimming generates dynamic pressure from arm strokes that can exceed the static rating. As a rule, only use a watch in water activities rated at at least double the expected depth equivalent — e.g. use a 10 ATM watch for activities where you'd only reach 30–40 m of effective pressure.

3

How IP and ATM Ratings Work Differently

Same goal, completely different testing methods and what they actually measure

IP and ATM ratings both describe water resistance — but they measure entirely different things using different test methods, different standards bodies, and different real-world implications. Understanding the gap between them is essential for choosing the right watch.

Aspect	IP Rating	ATM Rating
Core Definition
What it measures	Protection against both dust and water ingress — two separate measurements in one code	Protection against water pressure only — how much atmospheric pressure the watch can withstand
What "water protection" means	Type of water exposure: jets, splashes, or immersion — and whether dust is blocked	Equivalent depth of static water pressure the watch can survive
Dust protection included?	✅ Yes — first digit (IP6X = fully dust-tight)	❌ No — pressure only, no dust test conducted
Test Method
Test type	Jet spray test (IP65/66) or static immersion tank (IP67/68)	Static pressure tank — watch held stationary under the equivalent water pressure
Dynamic movement tested?	❌ Not tested — devices are stationary during the test	❌ Not tested — static pressure only, no arm-stroke simulation
Temperature of water in test	18–25 °C (fresh water, controlled lab)	Ambient temperature fresh water
Saltwater or chlorine tested?	❌ Fresh water only	❌ Fresh water only
Governing Standard
Standard body	IEC (International Electrotechnical Commission) — IEC 60529	ISO (International Organization for Standardization) — ISO 22810
Industry origin	Consumer electronics industry (phones, tablets, wearables)	Traditional watchmaking industry (mechanical and quartz watches)
Unit of measurement	Two-digit code: solid rating (0–6) + liquid rating (0–9)	Single number: atmospheres of pressure (1 ATM = 10 m depth equivalent)
Practical Implications for Watches
Can you swim with it?	IP67: not ideal. IP68: yes, within mfr depth spec. IP65/66: no	3 ATM: no. 5 ATM: yes (surface). 10 ATM: yes including water sports
Depth guidance?	Indirect — IP68 specifies depth but only as a lab test number	✅ Explicit — ATM directly converts to metres (1 ATM = 10 m)
Clarity for consumers	Tells you what type of water (jets vs. immersion) but not how deep	Tells you how deep but not what type of water contact is safe
Found on	Smartphones, smartwatches, electronics, industrial equipment	Traditional watches, sports watches, diving watches, rugged smartwatches

🔬

IP tells you the type of exposure

Is it protected against dust? Against jets? Against submersion? IP answers these with precision, but does not directly tell you how deep or for how long.

🌊

ATM tells you the pressure limit

How much water pressure can the watch take? ATM answers this clearly in depth metres, but says nothing about dust, jets, or dynamic water contact.

⚡

Together they tell the full story

The best smartwatches carry both. Samsung Galaxy Watch 7: IP68 + 5 ATM. Apple Watch Ultra: WR100 (10 ATM) + EN13319 dive standard. Both are needed for complete picture.

4

Which Is More Important for Smartwatches?

The case for IP ratings, ATM ratings, and why the best watches carry both

For smartwatches specifically, both ratings matter — but they serve different needs. If you only see one rating on a smartwatch spec sheet, here is how to interpret it and what it is missing.

IP Rating — Why It Matters for Smartwatches

IP is essential for everyday electronics protection

🌫️Smartwatches contain sensitive electronics — sensors, chips, batteries. Dust and grit can cause permanent damage. IP's first digit (dust protection) is unique to this rating and completely absent from ATM.
💦IP68 is now the minimum expected standard on any flagship smartwatch. It confirms the device has been tested for continuous immersion beyond 1 m — the scenario that matches real everyday life: drops in sinks, rain, showers.
🔬IP ratings are tested and certified by independent laboratories against IEC 60529. They are legally meaningful in most consumer protection jurisdictions.
📱Electronics regulators and smartphone standards universally use IP — meaning it is the most directly comparable number when comparing a smartwatch to a smartphone or tablet.

ATM Rating — Why It Matters for Smartwatches

ATM is essential for water sports and swim fitness

🏊IP68 says nothing about swimming capability. A watch can pass IP68 at 1.5 m and still fail under the repeated dynamic pressure of swimming strokes. ATM measures pressure tolerance, which is the critical factor for sustained water activity.
🎯5 ATM is the practical minimum for swim tracking. All swim-ready smartwatches — Garmin, Apple Watch (WR50 = 5 ATM), Samsung — carry a 5 ATM equivalent or higher, regardless of their IP rating.
🤿For snorkelling, open water swimming, or surfing, 10 ATM is the benchmark. The Apple Watch Ultra's WR100 rating (= 10 ATM) combined with EN13319 is what qualifies it for recreational diving — not its IP rating alone.
📐ATM converts directly to depth in metres, making it far more intuitive for athletes and divers assessing whether their watch can handle a specific activity.

🏆

Verdict: For Smartwatches, IP68 + 5 ATM Together Is the Gold Standard

IP68 ensures your smartwatch's electronics are fully sealed against both dust and water ingress for everyday life. 5 ATM (or higher) ensures it can handle the pressure of real water activities like lap swimming. If a smartwatch only shows one rating — check the spec sheet for the other before buying. The best wearables carry both. Examples: Samsung Galaxy Watch 7 (IP68 + 5 ATM), Apple Watch Series 11 (IP6X + WR50 = 5 ATM), Garmin Fenix 8 (10 ATM + MIL-SPEC).

5

Waterproof vs Water-Resistant — What's the Difference?

The two terms the watch industry uses — and what they actually mean

Water-resistant means a watch can withstand water exposure up to a specific tested limit — defined by either an IP or ATM rating — but it is not immune to water damage under all conditions. Gaskets age, seals degrade with heat and chemicals, and dynamic pressure from swimming exceeds static lab tests. Most watches on the market are water-resistant: they are rated to handle a specific amount of water, for a specific duration, under specific lab conditions, and nothing more. Waterproof, on the other hand, implies total, unconditional protection against water — and strictly speaking, no watch is truly waterproof. The ISO 22810 standard and IEC 60529 both prohibit manufacturers from using the word "waterproof" because it implies unlimited protection that no mechanical or electronic device can permanently guarantee. In practice, when a brand markets a watch as "waterproof," they mean it has a high water-resistance rating (typically 10 ATM / IP68 or above), but the same limitations on ageing seals, temperature, and chemical exposure still apply. The safest approach: treat every watch as water-resistant, not waterproof — check the rating, stay within its limits, rinse after salt or chlorine exposure, and service the seals regularly.

💧 Water-Resistant

Protected up to a tested limit. Rated by IP (IP67, IP68) or ATM (3 ATM, 5 ATM). Seals and gaskets can degrade. Performance depends on the watch being undamaged and regularly serviced. The accurate and honest term for virtually every watch on the market, from a budget fitness band to a professional dive watch.

🛡️ "Waterproof" (Marketing term)

Implies total, permanent protection — which no watch can guarantee. Used loosely in marketing for watches with high ATM ratings (10 ATM+) or IP68 certification. Not permitted under ISO 22810 or IEC 60529. Treat any "waterproof" claim as shorthand for "high water resistance" — and still check the actual IP and ATM numbers.

📋 Quick rule: No watch is 100% waterproof forever. All water resistance degrades over time with exposure to heat, chemicals, and physical wear. Rinse your watch after salt or chlorine exposure, avoid pressing buttons underwater on non-diver-rated watches, and have seals inspected annually if you swim regularly.