Watch Water Resistance: What Do 30M, 50M, 100M and 200M Mean?
Watch water resistance: what do 30M, 50M, 100M and 200M mean?
One of the most commonly misunderstood watch specifications is water resistance.
If a watch is marked 30M, 50M, 100M or 200M, it does not mean that you can safely dive with it to that exact depth.
The number indicates the level of resistance of the watch case to water pressure during testing, not the actual permitted diving depth.
That is why WATCHZ recommends treating the water-resistance rating as a level of protection for the watch, rather than as a direct instruction for swimming.
30M / 3 bar — basic protection
30M water resistance is the entry level of protection against water.
Such watches are primarily designed for everyday situations:
- rain;
- accidental splashes;
- minor contact with water.
A good example is a Seiko with 30 metres of water resistance:
Seiko SWR104P1
3 388 000 UZS
30M does not mean that you can dive to a depth of 30 metres. We do not recommend treating this level as water resistance intended for swimming or regular contact with water.
50M / 5 bar — higher everyday protection
50M provides a greater level of protection compared with 30M.
For example:
Casio MTP-B140D-2AVDF
937 500 UZS
Such watches are better protected against accidental contact with water, but the 50M marking still should not be interpreted literally.
50M does not mean that the watch is designed for diving to a depth of 50 metres.
If you plan to swim, it is better to check the manufacturer’s recommendations for the specific model separately.
100M / 10 bar — serious water resistance
100M represents a noticeably higher level of case protection.
For example:
Beverly Hills Polo Club BP3890X.390
2 125 000 UZS
Such watches are better suited to conditions where contact with water occurs more frequently.
But even here, we do not recommend using the rule:
“100M = you can safely swim with any watch”.
Case construction, the crown, buttons and the requirements of a specific manufacturer may differ.
Water resistance of 100M on its own also does not make a watch a diver’s watch.
200M / 20 bar — a high level of water resistance
A 200M rating indicates a high level of protection against water pressure.
For example, Orient Star:
Orient Star RE-AU0602E00B
17 098 000 UZS
However, even here it is important to distinguish between watches that simply have 200M water resistance and watches specifically designed for diving.
200M does not automatically mean that the watch is intended specifically for swimming or professional diving.
For diving models, the case construction, crown, bezel, legibility and compliance with special standards are also important.
Why shouldn’t metres be interpreted literally?
Water-resistance tests are carried out under controlled conditions.
In real life, a watch is additionally affected by:
- movement of the arm;
- impacts against the water;
- condition of the gaskets;
- age of the watch;
- temperature;
- position of the crown;
- previous repairs or battery replacement.
Therefore, a 50M rating does not mean an actual safe diving depth of 50 metres, and 100M does not mean 100 metres.
Water resistance can change over time
It is important to remember that the stated water resistance primarily applies to a properly functioning watch in normal condition.
Water tightness can be affected by:
- wear of the gaskets;
- impacts;
- damage to the crown;
- opening the caseback;
- battery replacement.
Therefore, if the watch regularly comes into contact with water, it is advisable to have its water resistance checked after servicing.
WATCHZ conclusion
The main rule is very simple:
30M, 50M, 100M and 200M are levels of water resistance, not literal permitted diving depths.
The higher the rating, the greater the potential protection of the case against water and pressure. But in real use, you need to consider the specific model, its construction, condition and the manufacturer’s recommendations.
That is why we do not recommend choosing a watch according to the principle:
“The more metres written on it — the deeper you can dive”.
It is better to choose the level of water resistance according to the conditions in which the watch will actually be used.
FAQ
Can you swim with a 30M watch?
We would not recommend it. This is primarily basic protection against accidental contact with water.
Does 50M mean you can dive to 50 metres?
No. This figure refers to test pressure, not the actual permitted depth.
Can you swim with a 100M watch?
Some manufacturers allow this for specific models, but you should not rely solely on the 100M marking. You need to check the manufacturer’s instructions.
Are all watches with 200M water resistance diver’s watches?
No. A 200M water-resistance rating alone does not mean that the watch meets the requirements for diving watches.