Are Garmin Forerunner 45 Waterproof? | 5 ATM Truth Check

Yes, it’s rated 5 ATM for swimming, so pool sessions are fine, but skip diving and high-pressure water.

If you’re asking whether the Garmin Forerunner 45 is “waterproof,” you’re probably thinking about real life: sweaty runs, surprise rain, handwashing, showers, and the odd swim. You want one straight answer, then the fine print that keeps your watch alive.

Here’s the deal: the Forerunner 45 is made to handle water in normal training situations, including swimming. At the same time, “waterproof” is a loaded word. A watch can be safe in a pool and still hate a hot shower or a high-pressure jet from a tap.

This article breaks down Garmin’s rating, what it means for daily use, what tends to cause leaks in sports watches, and the simple habits that keep water resistance working for years.

Are Garmin Forerunner 45 Waterproof? Water Rating And What It Covers

Garmin lists the Forerunner 45 with a water rating of 5 ATM, marked for swimming. You can see the “Swim, 5 ATM” water rating in the official specs for the device. Forerunner 45 owner’s manual specifications

That rating is the core of the answer. It means the watch is built to handle water pressure up to a test level that matches surface swimming use. It’s meant for rain, sweat, rinsing, and pool laps.

Still, “waterproof” gets used in casual talk to mean “nothing can hurt it.” No sports watch works like that. Water resistance is a set of seals, adhesives, and gaskets. Those parts can wear down, get damaged, or fail if the watch takes a hard hit.

So think of the Forerunner 45 as a “swim-ready” watch, not a dive computer.

What 5 ATM Means In Plain Terms

ATM is a pressure rating. It’s not a promise that you can strap the watch on and sit at 50 meters underwater for hours. It’s a lab rating used to sort watches into practical use bands.

For a Forerunner 45 owner, the question is simpler: “What can I do with it on?” Here’s the practical translation.

Activities That Fit The 5 ATM Use Case

• Rain and sweat: Safe. This is normal training wear.
• Handwashing and sink splashes: Safe, as long as you avoid blasting the watch with a sprayer at close range.
• Pool swimming: Safe. The rating is marked for swimming.
• Shallow water play: Safe when it’s gentle.

Activities That Create Extra Risk

• Diving and deep snorkeling: Not the target use for 5 ATM sports watches.
• High-speed water sports: Falls and surface impact can spike pressure at the seals.
• Hot showers, hot tubs, saunas: Heat can stress seals and adhesives, and soap can help water creep into gaps.
• Pressure jets: A strong stream aimed at the case or buttons is a common way to force water past seals.

Garmin Forerunner 45 Water Resistance In Daily Use

The Forerunner 45’s water rating is the starting point. Real life adds a few variables that decide how safe a given situation is. Most water damage stories come down to one of these:

• Buttons pressed underwater: Some designs handle it better than others. Pressing buttons can momentarily shift seals and let water in.
• Temperature swings: Heat can soften adhesives and change internal air pressure.
• Soap, shampoo, sunscreen: These can reduce surface tension and help water push into tiny gaps.
• Age and wear: Seals degrade over time, especially with daily sweat, skin oils, and salt exposure.
• Impact: A sharp hit can crack the case, shift a seam, or create a hairline leak path.

If your use is mostly running, gym work, and the occasional swim, the Forerunner 45’s design lines up well. If your use is daily hot showers with soap plus frequent ocean swims, treat it with more care and rinse it often.

Is Showering With A Forerunner 45 A Good Idea?

Many people do it without trouble. The risk comes from heat and chemicals, not the water alone. Hot water warms the case, and soaps can work their way around the edges over time.

If you want the safest habit, take it off for showers and put it back on after. If you keep it on in a quick shower now and then, avoid heavy soap contact with the watch and rinse it afterward with cool fresh water.

Can You Swim Laps With It?

Yes. The Forerunner 45 is rated for swimming, and the “Swim, 5 ATM” label is Garmin’s cue that pool use is in scope. Garmin Forerunner 45 product specs

For lap swimmers, the bigger worry is not water getting in. It’s buildup. Chlorine, salt, and grit can collect around buttons and seams. That’s why a rinse after a swim matters so much.

What To Do Before Water Workouts

A minute of prep lowers your risk a lot. Do these quick checks before swimming, beach time, or a wet race.

Quick Pre-Swim Check

1. Scan the case: Look for cracks, chips, or a lifted edge near the screen.
2. Check the strap pins: Make sure the band is seated and not loose.
3. Clean the buttons: If they feel gritty, rinse the watch and gently work the buttons above water.
4. Avoid charging just before swimming: Let the watch cool and dry if it was charging in a warm spot.

If you see a crack or the screen looks slightly lifted, don’t test your luck in water. Even a tiny opening can turn into a full leak once you start moving in the pool.

Water Use Cheat Sheet For The Forerunner 45

This table is meant to answer the common “Can I wear it for this?” questions fast, without forcing you to hunt through forums.

Situation	Wear It?	Notes That Matter
Running in rain	Yes	Wipe it dry after, especially around buttons.
Sweaty gym sessions	Yes	Rinse if salt buildup is visible, then dry.
Handwashing and sink splashes	Yes	Avoid aiming a strong sprayer at the seams.
Pool lap swimming	Yes	Rinse with fresh water after to reduce chlorine wear.
Open-water swimming near shore	Yes, with care	Rinse well after saltwater; check buttons for grit.
Showering (warm water, soap)	Sometimes	Heat and soap raise risk; rinse in cool water after.
Hot tub or sauna	No	Heat stresses seals and adhesives over repeated exposure.
Cliff jumps or hard cannonballs	No	Surface impact can spike pressure at the seals.
Water skiing or wakeboarding	No	High-speed impact against water can exceed the design use case.

How To Keep The Water Resistance Working Longer

Most people never think about water resistance until it fails. A few simple habits cut the odds of failure, and they don’t take much effort.

Rinse After Pool Or Ocean Use

Chlorine and salt don’t just irritate skin. They dry out materials and can leave deposits in tiny gaps around buttons. After swimming, rinse the watch under gentle fresh water, then pat it dry.

Keep Soap Off The Watch

Soaps and shampoos can sneak into seams more easily than plain water. If you wear the watch while washing up, try to keep lather away from the watch body. Then rinse it in fresh water and dry it with a soft cloth.

Don’t Push Buttons Underwater

If you need to start or stop an activity, do it before you get in, or raise your wrist above the surface first. This habit alone prevents a lot of leaks across many watch brands.

Dry It Before Charging

Charging is where moisture can cause trouble fast. Even small droplets can create corrosion over time. After any water exposure, dry the watch fully before you connect the cable.

Watch Out For Impacts

Water resistance assumes the case is intact. If your watch takes a hard hit on tile, concrete, or rocks, treat that as a warning sign. Check for cracks and avoid swimming until you’re confident it’s still sealed.

Signs Your Watch Should Stay Out Of Water

Water damage is easier to prevent than to fix. If you spot any of these, keep the watch dry until it’s checked or replaced.

• Fogging under the screen: Even light haze can be a sign of moisture inside.
• Buttons that feel sticky or gritty: Grit can damage seals when pressed.
• Screen lifting at an edge: A lifted seam is a direct water path.
• Charging issues after getting wet: Moisture near the contacts can cause corrosion.
• Random shutdowns after swimming: Electronics and moisture don’t mix.

If you do see fogging, power the watch off, dry the exterior, and keep it in a dry place. Avoid heat sources like hair dryers. Strong heat can warp parts and make sealing worse.

Care Routine After Water Exposure

This is the simple routine that fits most owners. It keeps the watch clean, reduces residue, and lowers the chance of seal wear.

When	What To Do	Why It Helps
After pool swim	Rinse with fresh water, pat dry	Reduces chlorine residue around seams and buttons
After ocean swim	Rinse longer, check buttons for grit	Salt crystals and sand can grind seals over time
After heavy sweat	Wipe the back and strap, let it air dry	Salt and skin oils build up near contact points
Before charging	Confirm it’s fully dry	Moisture near contacts can lead to corrosion
Weekly	Quick gentle rinse, soft cloth dry	Stops residue from turning into crust around edges
After a hard drop	Inspect case, avoid water until confident	Impact can create hairline cracks you can’t feel

When You Might Want A Higher Water Rating

The Forerunner 45’s 5 ATM rating fits most runners and casual swimmers. If your routine includes repeated high-impact water use, you may be happier with a device rated for deeper water use.

Here are common reasons to step up:

• You do frequent open-water swims with waves and surface impact.
• You spend time in fast water sports where wipeouts are normal.
• You want a watch that’s built with diving use in mind.

If none of that sounds like you, the Forerunner 45 is a solid match. Wear it in the rain, train hard, and take it in the pool. Just treat hot water, harsh chemicals, and pressure jets as the watch’s weak spots.

Answer Check For Everyday Buyers

If you’re deciding whether to buy the Forerunner 45 or keep wearing yours around water, this is the practical answer:

• Pool laps: Fine.
• Rainy runs: Fine.
• Shower use: It can work, but it adds risk over time due to heat and soap.
• Diving and high-impact water sports: Skip.

Stick to the care routine, avoid button presses underwater, and dry it before charging. Those habits do more than any marketing label.