Solutions for fogged glass on Casio watches

Does your Casio watch look like it’s got water in it? Is it fogged up or is it moisture inside the glass? Good questions. Maybe it happened to one of you. It can happen to you with a Casio G-Shock, with a Casio Edifice, or with Casio Pro Trek watches… There is no distinction between models and it can even happen in those models with 200m water resistance. Do we have to worry and take them to the technical service? Let’s see it.

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Official information from Casio on the problem: Why does the inside of the crystal on a Casio watch fog up?

The first thing we have to do is find the official information from Casio about it: What should I do if the inside of the glass fogs up?

“The inside surface of the crystal can cloud over when exposing the watch to a sudden drop in temperature. There is no problem if the glass defogs relatively quickly. Sudden and extreme changes in temperature (such as when entering an air-conditioned room in summer and standing near the outlet of the air conditioner, or leaving a heated room in winter and allowing the clock to enter in contact with snow) can cause the glass to take longer to defog. If the glass does not defog or if you feel moisture inside the glass, stop using the watch immediately and take it to the original dealer or an authorized CASIO service center.”

  • This information can also be found in the Casio manuals for each watch. You can check them online by entering the module number on the following page: Clock manual files.

It seems that to some extent it is normal for a sudden change in temperature if the glass defogs in a few minutes, no problem. If it stays like this… There is a problem and you must take it to the technical service center.

What is the Difference between fogged glass and glass with moisture in watches?

Difference between fogged glass and glass with moisture in watches

Fogged glass is not the same as glass with humidity… Fogged glass means that we have water vapor (water in a gaseous state) that has been formed by the sudden change in temperature (there are no drops of water) and ” Humidity” means that we have water in a liquid state that has entered the clock from the outside.

You may be interested in these articles with other problems of your Casio watches that we have solved:

Is there more information about it on the Internet?

In the forum dedicated to watches watchuseek, they have carried out an interesting experiment with several Casio G-Shock watches to verify everything we are counting.

With the fogged glass there is no problem and it is not necessary to return the watch or make use of the guarantee. Your Casio is not dead, It’s normal. It seems that Casio accepts returns in this case, but it will depend on where you bought it.

You can even try it yourself at home at your own risk. You just have to take a bucket with hot water and another with very cold ice water. You can put the watches in one of the buckets for about 10, to 15 minutes and then transfer them to the other bowl. You will see the result… if you have courage. Nothing irreversible should happen. The foggy glass should return to normal in several minutes.

Is it a situation that is going to happen quickly in real life? Well, probably not… we can’t think of many cases in which these sudden temperature changes occur.

Some example: you are on a frozen lake in Finland or Siberia and then you put your Casio in a Finnish sauna. You are in Madrid at 40 degrees in summer and suddenly you put your wrist with the watch in the freezer. 

You have lost yourself in the mountains in the middle of winter, everything is full of snow and suddenly you find yourself in the mountain refuge with the heating set to 35 °C. 

You are in the warm bathtub, with a lot of steam and with a drink in your hand, and… You have forgotten the ice cubes! and you have to put your hand in the freezer to the bottom and you spend several minutes looking for the ice cubes… Result? The inner glass of your Casio watch is going to fog up…

Solutions for fogged glass on Casio watches

Solutions for fogged glass on Casio watches

Attention! If you are facing the problem of fogged glass on your Casio watch, don’t worry. Here are some practical solutions and helpful tips to fix this problem.

There are a few different methods you can use to fix a foggy watch glass. Here are a few options:

1. Understand the problem

First, it’s important to understand why the glass on your Casio watch fogs up. This can occur due to sudden and extreme changes in temperature. If the glass defogs quickly, there is no problem. But if it persists, you need to take action.

Solution #1

Keep the watch in front of the sun for a couple of minutes. In this way, the sun’s heat will take the fog out of your watch and your problem will be solved.

Solution #2

If Fogg does not disappear in the first method then try out this step which is a little technical and you have to be careful doing this.

I’m going to show you how to get rid of this pesky fog or condensation inside of the screen. Let’s go..

Take off the four screws right in the back there. Pretty simple. Use a size zero screwdriver, and remove the back plate.

The glass of your Casio watch fogs up: Causes, solutions, and tips

You’ll see that it’s pretty easy to remove. I use a little pin and poke right into the little void there, push it towards me, and that should open up the module.

Now take out the little frame inside the module to get access to the glass where you have all the fogg.

  • Take a fine microfiber cloth and delicately wipe down the innards of that watch glass. Give the boot to any pesky dirt or debris causing the dreaded fogging.
  • Now, time to do a soft massage on that watch glass. Dab a toothpaste onto the watch glass’s inner surface. Gently massage it in using that same microfiber cloth. The toothpaste’s magic will whisk away any stubborn grime that shall leave the glass gleaming.
  • Now comes the grand finale, my watch aficionado amigo. Lay your hands on a defogger spray or solution, tailor-made to tame glass fog. With a spritz or a dab, you’re making sure that your watch’s glass fends off the future foggy fiestas. No more condensation/fogg!

After doing the above task fit back the module and put in the back plate and make sure to tighten the screws.

Solution #3. Take it to the technical service

If the glass does not defog or if you feel moisture inside the glass, stop using the watch immediately and take it to the original dealer or an authorized CASIO service center.

4. Avoid sudden temperature changes

Try to avoid exposing your watch to sudden changes in temperature, such as going from a very cold environment to a very hot one. This can prevent fogging in the first place.

Do not confuse fogging with humidity

Fundamental! Foggy glass is not the same as glass with moisture. Foggy glass means water vapor, while “moisture” means water in a liquid state that has entered the watch. Moisture requires immediate attention.

Consult the manual of the watch

You can find specific information on fogging in the Casio manuals for each watch. Consult online by entering the module number on the Casio manual page.


The first thing is not to panic. You have to try the solutions that we have mentioned and give the clock a little time to return to its normal situation. In case it is not solved, the Casio technical service or a watchmaker you trust is the best solution.

Analyze the following table in case your watch has any of these problems:

Misted glassGlass fogging due to sudden changes in temperature.Avoid extreme temperature changes, or take it to a technical service if it persists.
Depleted batteryThe watch stops working or shows signs of erratic operation.Change the battery at an authorized technical service center.
Bluetooth Connection ProblemsDifficulty connecting the watch with a device via Bluetooth.Check compatibility, update software, or reboot both devices.
Glass with moisturePresence of liquid water inside the watch.Take it immediately to the technical service.
Belt Worn or RotatedWear or breakage of the watch strap.Replace the strap at a service center or with a compatible one.
Problems with Solar ChargingThe sundial does not charge or does not seem to be working properly.Be sure to expose it to a suitable light source and refer to the manual for instructions.
Time InaccuracyThe clock does not display the correct time or drifts constantly.Adjust the time manually or use the automatic synchronization function if available.
Buttons Not RespondingWatch buttons are unresponsive or work erratically.Take it to the technical service, since it could be an internal problem.
Alarm ProblemsThe alarm does not sound or is not set correctly.Check the alarm settings in the manual and make sure it is activated.
Compromised Water ResistanceWater infiltration in waterproof models.Avoid exposure to depths or pressures not recommended and take it to the technical service if there is infiltration.

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Has it happened to you with your Casio watch or with any other type of watch? Leave a comment with your experience.

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