When was the last time you cleaned your smartwatch? These are devices you wear 24/7, and if you took off your watch right now, there’s a good chance you’d find dead skin, sweat, oil, and grime all over it. A gunky sensor array isn’t the best for health tracking, and crusty charging contacts are also less than ideal. If you’ve experienced any skin irritation or smelled something funky — this may be why.

Plus, I hate to break it to you, but your straps are also filthier than you think. A recent study found that nearly 95 percent of smartwatch wristbands contained high levels of bacteria, including Staphylococcus, E.coli, and Pseudomonas — particularly on porous materials like rubber, plastic, and fabric.

The good news is that cleaning your smartwatch and straps is relatively simple. All you need is about five to 10 minutes, a few cleaning materials, and a microfiber cloth. (No, showering with the device on does not count.)

Cleaning the smartwatch itself

First things first: power down your watch. Many smartwatches these days are water-resistant or swimproof, but you’ve also spent a good chunk on this device. It doesn’t hurt to play it safe.

Cleaning the display is a lot like cleaning your phone screen. All you need is a microfiber cloth for polishing off the dust, dirt, and grime. If you want to get fancy, you can always use a gentle solution of hand soap and water. Just spritz or dab it onto the microfiber cloth — not the display itself — and then clean.

If the back of your watch isn’t too grody, a microfiber cloth will suffice here, too. Wet wipes that contain 70 percent isopropyl alcohol, disinfectant, or are specially made for electronics are also a good option if you’ve let the back get very crusty. (No judgment, it happens.) If you’ve got a watch that has deep charging grooves like the charging port on the Garmin pictured here, you may want to go in with a damp cotton swab or a soft bristle toothbrush because those grooves are a magnet for dead skin.

As for how often you need to do this, it depends. I like to periodically check the back of my watches when I take them off to shower. If I can see dead skin, it’s time for a good wipe-down. There’s also the sniff test. If it smells even a little funky, it’s time.

Bands

Smartwatch bands are a whole other beast. How you clean them will depend on the material itself. It’ll also come down to how much you spent on said band. Personally, I’ve got no qualms about sticking fabric or nylon bands that I bought for $2 off Amazon in a mesh laundry bag and throwing them in the washing machine on delicate. (Just let it air dry; don’t stick it in the dryer.) I would never do that with a leather band.

Plastic, rubber, and silicone bands

These are the easiest to clean. For a quick clean, rinse them in water with some gentle hand or facial soap. You can also give them a quick once-over with a disinfectant wipe if you’re worried about germs. A toothbrush or toothpick can help with stuck-on grime in watch strap holes. In any case, either air dry or pat dry with a lint-free cloth.

Fabric or Nylon bands

As I mentioned, you can always chuck these in a mesh laundry bag with the rest of your wash, so long as you make sure you don’t put them in the dryer. That can cause shrinkage and fraying.

Otherwise, you can hand wash in cold water with a gentle hand soap. Rinse, and then let air dry. If you’ve got a woven fabric band, I would opt for handwashing because it’ll last longer.

Metal or stainless steel bands

If you wear metal bands every day, you want to give these a deep clean about once a month. The good news is that you don’t really have to worry too much about disinfecting. The same study that found plastic and rubber bands to be a breeding ground for bacteria found that it’s hard for bacteria to thrive on metal bands.

What you’ll need is:

• a microfiber or lint-free cloth
• soft bristle toothbrush
• dishwashing liquid
• small bowl

First, remove the band from the watch and give it a good wipe-down with a microfiber cloth. That’ll get rid of initial grime, oil, and dust. Rinse the band under room-temperature tap water.

Next, fill a bowl with lukewarm water. You want to ensure it’s lukewarm because extreme temperatures can cause warping. Mix in a few drops of dishwashing liquid (a gentle hand soap will also work). Dip your soft-bristled toothbrush into the bowl and gently scrub the band to get rid of grease, oil, and dirt. You don’t have to use a lot of pressure, as soft bristles aren’t likely to leave scratches.

Once you’re done scrubbing, rinse with lukewarm water. Make sure to check between links for any soapy residue. The last thing you want is any kind of film. After you’re done rinsing, pat dry the remaining surface moisture. You want to be thorough here, too, since too much moisture could lead to rust and corrosion.

Leave to air dry for 30 minutes to an hour on a cloth or paper towel before putting it back on. That’ll help ensure any remaining moisture you can’t reach will get the chance to fully evaporate.

Leather bands

Like metal, leather bands require a bit more care than fabric or silicone. Here’s what you’ll need:

• Two microfiber cloths
• Gentle liquid soap
• Leather conditioner (optional)

The key things to keep in mind with leather straps are to be gentle and conservative.

First, take the first microfiber cloth and gently wipe off any dirt or dust. The goal is to remove any dry particles before you go in with moisture to prevent unnecessary damage.

Next, take your second microfiber cloth and dampen it with water. Spritzing with a spray bottle is helpful since you can more easily control how wet it gets. Leather is sensitive to water, so you really don’t want to get it too wet. Add a drop of liquid soap and work it into the cloth. Less is more.

Gently massage the leather strap with circular motions. Do not scrub. I repeat, do not scrub. Imagine you’re petting a sleeping kitten, and you don’t want to wake them.

Once you’re done, spritz the first, dry microfiber cloth with plain water and do the same — this is to “rinse” the band. When you’re done, let the strap air dry in an area that’s not in direct sunlight or heat.

At this point, you can choose to use a leather conditioner to keep the strap supple and prevent cracking. Ideally, pick one that’s specifically made for watch straps or leather clothing items (belts, bags, etc.). Remember to spot test so you don’t risk discoloration, and follow the instructions for that specific conditioner.

My last tip for leather bands is to swap straps often. Get a fabric or silicone band for your workouts because leather and exercise do not mix well. The sweatier you get, the more often you’ll have to clean them. Also, don’t wash the dishes or otherwise immerse your hands in water with a leather strap on unless you’re wearing elbow-length kitchen gloves. Unless, of course, you’re looking for an excuse to buy a new strap.