Can You Take Your Phone in a Sauna? What Apple Says
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Short answer: you can, but Apple says not to. Apple designs iPhone for use at 0°C to 35°C (32°F to 95°F) and storage up to 45°C (113°F), according to its temperature guidance. A Finnish sauna runs at 70-100°C (158-212°F). Apple’s water resistance page also lists “using your iPhone in a sauna or steam room” among the things to avoid.
People bring the phone in for music, a podcast, the time, or to stay reachable. All of that works with the phone outside the door, and this guide shows how.
In This Guide
- Can you take your phone into a sauna?
- What happens to a phone in a sauna?
- Why steam is the bigger problem for a phone
- Is 10 minutes in the sauna OK for a phone?
- Infrared saunas and steam rooms
- Do sauna phone pouches and cooler bags work?
- My phone overheated in the sauna: what now?
- How to keep music and round cues with the phone outside
- Phones in a public sauna
- Frequently asked questions
Can you take your phone into a sauna?
Physically, yes. Nothing stops you, and many phones come through a short visit. But Apple rates iPhone for air no hotter than 35°C (95°F) during use and names saunas and steam rooms as places to avoid. Samsung gives the same 32-95°F range for Galaxy phones.
The numbers side by side:
| Temperature | |
|---|---|
| iPhone and Galaxy, recommended during use | 0-35°C (32-95°F) |
| iPhone, recommended storage | -20°C to 45°C (-4°F to 113°F) |
| Steam room | 40-50°C (104-122°F) |
| Infrared sauna | 45-65°C (113-149°F) |
| Finnish sauna, near the top bench | 80-100°C (176-212°F) |
Even the floor of a Finnish sauna is no refuge. The top bench can be 20-30°C warmer than the floor, which still leaves the floor of an 80°C room well above 35°C.
What happens to a phone in a sauna?
A hot phone protects itself first. Apple lists what you may see when an iPhone runs above its normal range: charging slows or stops, the display dims or goes black, the cellular signal weakens, the camera flash turns off, and apps slow down. Past a certain point the phone shows a temperature warning and stops being usable until it cools.
Those are the visible effects, and they pass once the phone is back at room temperature. The one that does not pass is battery wear. Apple says plainly that using a device in very hot conditions “can permanently shorten battery life”. Lithium-ion cells age faster in heat, and a weekly sauna habit adds that up across a year.
Why steam is the bigger problem for a phone
Moisture is the less obvious risk. When you carry a room-temperature phone into a hot sauna, the phone is the coldest thing in the room, and humid air condenses on cold surfaces. Think of glasses fogging up as you walk in.
We worked out the dew point of typical sauna air, the temperature at which its moisture starts to condense:
| Sauna air | Dew point |
|---|---|
| 80°C (176°F), 10% humidity, dry | about 32°C (90°F) |
| 80°C (176°F), 15% humidity | about 39°C (102°F) |
| 80°C (176°F), 20% humidity, after löyly | about 45°C (113°F) |
| 80°C (176°F), 30% humidity, a big löyly | about 53°C (127°F) |
| Steam room, 45°C (113°F), close to 100% | about 45°C (113°F) |
A phone that walks in at 22°C (72°F) is below every one of those. Water forms on the glass, the camera and the openings for the speaker, microphone and charging port until the phone warms past the dew point. Each löyly raises the humidity, and with it the dew point, so the cycle repeats through the evening.
IP68 water resistance does not cover this. Apple says resistance “might decrease as a result of normal wear”, that liquid damage is not covered by the warranty, and separately warns against using an iPhone “in extremely humid conditions”.
Is 10 minutes in the sauna OK for a phone?
Often the phone survives it, which is why people keep trying. But the room is outside the phone’s rated range from the moment you walk in, and in a Finnish sauna 10 minutes can be enough for the phone itself to heat up and show the first heat behavior, a dimmed screen or a warning. One short visit is unlikely to kill a phone. The battery wear and the moisture add up with each visit, and Apple’s warranty does not cover either.
If you take it in anyway, keep it in a shaded spot low down, away from the heater and the stones, never on the top bench, and bring it out at the first temperature warning.
Infrared saunas and steam rooms
An infrared sauna is easier on a phone than a Finnish one. The air is cooler at 45-65°C (113-149°F) and dry, since there is no water on stones, so condensation is not the issue. It is still above the 35°C rating, and infrared panels warm whatever faces them, so a phone left in front of a panel heats faster than the air suggests. Infrared sessions also tend to run longer.
A steam room is cooler still at 40-50°C (104-122°F), but close to 100% humidity, and Apple names steam rooms alongside saunas. Of the three, it is the worst place for a phone: the dew point equals the room temperature, so the phone collects water until it has warmed to the room, and by then it is past its rating anyway.
Do sauna phone pouches and cooler bags work?
Neither changes Apple’s guidance. A “sauna-safe” pouch insulates the phone, which slows how fast it heats up, but it also keeps the heat in once it gets there. That buys a few minutes, but the phone is still in a room far above its rating.
A cooler bag with an ice pack is a common tip online. It keeps the phone cooler for a while, but it also makes the phone even colder than the room, which is what draws condensation. Open the bag in a humid sauna and the cold phone fogs up. If the phone has to be near the door, outside the door is better than inside it in a bag.
My phone overheated in the sauna: what now?
Follow Apple’s steps for the temperature warning: turn the phone off, move it somewhere cooler, and let it cool down. A few more points help:
- Cool it at room temperature. Not in a fridge, freezer, cold plunge or snowbank. A fast drop from hot to cold creates condensation inside
- Don’t charge it hot. The phone will refuse or slow charging until it cools anyway
- If it got wet, wipe it with a soft cloth, let it dry in moving air, and wait at least 5 hours before charging with a cable, as Apple advises
- Watch for a muffled speaker or a liquid warning when you plug something in. Both mean water got into a port
Once it is cool and dry, the phone usually works as before. If it shows battery or display problems afterward, that is worth a visit to Apple Support.
How to keep music and round cues with the phone outside
Most people bring the phone in for sound or for the time. Neither needs the phone in the heat.
Sound through the sauna, not from the phone. The phone can stay outside and play through:
- A Bluetooth or AirPlay speaker outside the door, turned up a little. A wooden door softens it, which often suits sauna audio anyway
- The sauna’s own speakers. Many new home saunas come with heat-rated speakers in the wall or ceiling and a Bluetooth receiver outside the room. If yours does not, an installer can add one. Our guide to making an electric sauna feel wood-fired covers sound in the room
Know when the round is over without looking. A phone timer needs you to look at it, which is why the phone ends up on the bench. Cues you can hear solve that. A chime at the end of each round and cool-down, played through the same speaker, lets you keep your eyes closed. Our guide to timing sauna rounds compares the options, and the free web sauna timer does it in any browser.
If you want something on your wrist, Apple Watch can show the round and your heart rate, though Apple rates it for the same 35°C on most models. Read can you wear an Apple Watch in a sauna before you decide.
If you need to be reachable, leave the phone just outside the door with the ringer on. Between rounds, while you cool down, is a natural time to check it.
This is the setup Sauna Assistant is built around. You start a session once, the phone stays outside, and it plays one of 17 ambient themes and the round and cool-down cues through your sauna’s speakers over Bluetooth or AirPlay. The play, pause and next buttons on a connected speaker or remote pause, resume and skip rounds, and the lock screen shows where you are when you step out.
Phones in a public sauna
In gyms, spas and public saunas, the question is usually settled by a sign on the door. Many ban phones in the sauna because of cameras: people are in towels or less, and nobody wants to wonder whether they are in someone’s photo. Where phones are allowed, calls and speaker audio still are not welcome. Leave it in the locker and keep the sauna quiet for everyone.
Frequently asked questions
Can you take your phone into a sauna?
You can, but Apple advises against it. Apple designs iPhone for use at 0°C to 35°C (32-95°F) and lists using an iPhone in a sauna or steam room among the things to avoid. A Finnish sauna runs at 70-100°C, so the phone is far outside its rated range. Leave it outside the door instead.
Can I bring my phone in the sauna for 10 minutes?
Many phones survive 10 minutes, but a sauna is outside the manufacturer’s rating from the first minute. In a Finnish sauna the phone can heat up enough within that time to dim the screen or show a temperature warning. The real cost is gradual: heat wears the battery permanently and steam can get into the ports.
Will an iPhone be OK in the sauna?
An iPhone will usually protect itself by slowing charging, dimming the display and eventually showing a temperature warning. Apple says using it in very hot conditions can permanently shorten battery life, and liquid damage is not covered by the warranty. One short visit is unlikely to kill it; regular visits add up.
Can you take your phone in an infrared sauna?
An infrared sauna is gentler on a phone than a Finnish sauna, at 45-65°C (113-149°F) with dry air. It is still above the 35°C rating for iPhone and Galaxy phones, and a phone facing an infrared panel heats faster than the air around it. Keep it outside or out of the panels’ line.
Can you take your phone in a steam room?
It is the worst of the three for a phone. A steam room is only 40-50°C, but close to 100% humidity, so moisture condenses on anything cooler than the room, including your phone. Apple names steam rooms specifically, and water resistance wears with age.
Does IP68 water resistance protect a phone in a sauna?
No. IP68 is tested in a lab by holding the phone under still water, up to 6 meters for 30 minutes on recent iPhones. It says nothing about heat, and Apple warns against both saunas and extremely humid conditions. Water resistance also decreases with normal wear, and liquid damage is not covered by Apple’s warranty.
How do you listen to music in the sauna without your phone?
Leave the phone outside and play through a speaker: a Bluetooth or AirPlay speaker just outside the door, or heat-rated speakers built into the sauna with a receiver outside. A sauna app such as Sauna Assistant can play ambient sound and round cues through the same speaker.