Excessive heat can cause a number of issues with your smartphone, potentially causing damage or decreased performance. Understanding why phones overheat and the potential consequences can help you prevent problems and know how to respond if your phone does get too hot.
Why do phones overheat?
There are several common causes of overheating in smartphones:
- Using resource-intensive apps, especially for extended periods
- Charging with quick chargers that produce more heat
- Direct sunlight or hot environments
- Poor airflow if blocked or in a confined space
- Old batteries that can no longer handle heat efficiently
- Too many background apps running
- Hardware issues or defective battery
Newer phones are designed to withstand reasonable amounts of heat from typical use. But pushing the hardware too much with gaming, multitasking, or other heavy usage can still cause overheating in any phone over time.
What are the effects of overheating on a smartphone?
Excessive heat impacts your phone in several ways:
Battery life and charging
Heat causes more battery drain. A hot phone battery will lose charge faster than a cool one. Heat also slows down charging. It is safe for batteries to charge at cooler temperatures, so your phone will charge up quicker if not overheated.
Component damage
The delicate electronics in your phone can be damaged by sustained high temperatures. This is especially true for the processor, RAM, and other chips. Degradation of these components through overheating can cause permanent performance issues or even total component failure over time.
Display effects
OLED smartphone displays can exhibit temporary burn-in if overheated. This can fade away if the heat stress stops. But high sustained heat can lead to permanent screen burn-in or other display defects.
Slowdowns and crashes
Overheating induces throttling in the processor, RAM, and other components to try to cool things down. But this comes at the cost of slower performance and lag. Severe cases can lead to freezing, crashing, and reboots too.
Degraded battery
Lithium-ion batteries slowly deteriorate through normal use. But high heat accelerates capacity loss, shortening the battery lifespan. Batteries may need to be replaced sooner if overheated frequently.
What temperature is too hot for a phone?
There is no one “too hot” threshold since heat tolerances depend on phone design and materials. But some general temperature guidelines for Android and iOS devices are:
| 100°F – 113°F | Warm but ok for short periods |
| 113°F – 122°F | Very warm, risk of performance throttling |
| 122°F – 140°F | Hot, throttling likely, use cautiously |
| Over 140°F | Extremely hot, avoid use and charging until cooled |
As a good rule of thumb, if the phone feels very warm or hot to the touch, it is likely overheating.
How can I keep my phone from overheating?
Use the following cooling strategies to prevent your phone from overheating in the first place:
- Avoid intensive gaming or multitasking during charging
- Close background apps not in use
- Turn off Bluetooth and other antennas when not needed
- Remove protective cases periodically
- Point fans at your phone to cool it
- Keep the phone out of confined spaces and direct sun
- Disable auto-updates and syncing
- Turn down screen brightness
Avoiding prolonged intensive workloads and improved ventilation are key to keeping your phone operating at safe temperatures.
What should I do if my phone overheats?
If your phone feels excessively hot to the touch, follow these steps:
- Stop phone use immediately if possible
- Turn off the display screen
- Close all apps
- Turn on airplane mode
- Place the device in shade or air conditioned room
- Point a fan at the phone
- Remove protective case temporarily
- Avoid charging until cooled down
Waiting for the phone to cool before resuming use will minimize any potential damage from overheating. If the phone doesn’t cool down on its own, contact manufacturer support.
When should I be concerned about overheating?
Overheating is usually not a serious issue if occasional and temporary. But seek help from the manufacturer if you notice any of the following:
- Phone frequently gets hot during normal use
- Heat persists even after screen off and charging stopped
- Unusual behavior like freezing, crashes, or restarts
- Physical swelling of the battery
- Burning plastic smell
- Discoloration on screen or back
- Fast battery draining even when cool
Chronic overheating, heat that persists unabated, or any physical changes from heat can indicate hardware defects covered by warranty.
Does fast charging make my phone hotter?
Yes, quick charging does produce more heat. Fast charging provides higher voltage and current to charge the battery faster. But this increased power throughput generates excess heat energy as a byproduct.
Quick charge systems are designed to keep this heating within safe ranges. However, the battery and phone overall run hotter compared to slower 5W chargers.
Use fast charging cautiously and avoid when phone is already warm. Slower wireless or wired charging produces minimal heat in comparison.
Can leaving my phone in a hot car damage it?
Yes, exposing your phone to high temperatures inside a car can certainly damage it. The interior of a parked car can reach oven-like temperatures over 150°F on hot sunny days. Some effects of leaving a phone inside a hot car include:
- Battery capacity decrease
- Battery swelling or leaks
- Component damage
- Screen malfunction
- Warping or deformation
Phones left in cars on hot days should be shielded from direct sun exposure. Avoid use until the phone has cooled down to room temperature.
Does wirelessly charging my phone make it hot?
Wireless charging does generate slightly more heat than wired charging, but not substantially. The induction coil used to transmit energy wirelessly does produce some excess heat.
However, most heat during charging comes from the battery itself as it rapidly charges. So both wireless and wired quick charging will make your phone similarly hot overall.
Slower 5W wireless charging produces minimal heating compared to 10W or 15W fast wireless charging.
Should I use my phone while it’s charging?
It’s best to avoid extensive use of your phone while charging when possible. Charging alone will heat up your phone somewhat. Simultaneous charging and heavy usage like gaming or streaming can compound this effect, leading to overheating.
If you do need to use the phone while charging, follow these precautions:
- Use a slower charger
- Close unused apps
- Turn down screen brightness
- Disable background syncing
- Take periodic breaks from use
- Stop charging if phone gets hot
Avoid prolonged intensive usage until charging is completed to minimize overheating risk.
Does phone case material affect overheating?
The material and thickness of your phone case can impact heat buildup and cooling. Some guidelines for cases are:
| Plastic | Decent heat insulation |
| Silicone | Moderate insulation, grip attracts heat |
| Leather | Good insulation, poorer grip |
| Metal | Minimal insulation, case absorbs heat |
| No case | Best ventilation and cooling |
Thicker cases generally retain more heat. Periodically removing the case can improve airflow and cooling if overheating is an issue.
Can a defective battery cause overheating?
Yes, lithium-ion batteries that are defective or damaged internally can overheat. Some signs of a battery defect causing heat issues:
- Heat concentrates in one area, like the middle
- Phone gets hot despite mild use
- Overheating problems begin suddenly
- Swelling or discoloration on battery
If you suspect the battery is the culprit, discontinue use and contact manufacturer support for potential replacement under warranty.
Is it safe to use my phone while it’s hot?
It’s best to avoid using your phone if it feels excessively hot. The hotter the phone, the more likely performance will suffer from thermal throttling. Prolonged extreme heat can lead to crashes, restarts, or even permanent component damage in severe cases.
Wait for the phone to cool down through the steps mentioned earlier before resuming normal use. A warm phone is fine, but a very hot one needs to cool off.
Can I fix an overheating phone myself?
There is little you can do yourself to fix an intrinsically overheating phone beyond general cooling measures. But here are some self-remedies to try:
- Update software in case it fixes a bug causing overheating
- Use a light case or no case
- Clean out phone charge port and vents
- Replace battery if old or worn out
- Turn off background processes and features
- Limit gaming, streaming, and multitasking
For persistent overheating or if these steps don’t help, contact the manufacturer as a hardware defect may need repair.
Does underclocking or undervolting fix overheating?
Underclocking reduces CPU speeds while undervolting lowers operating voltage. Both techniques generate less heat by limiting phone performance. They can potentially reduce operating temperatures.
However, software mods come with risks like crashes or instabilities. Hardware defects causing overheating still need professional repair. Only use underclocking/undervolting if you fully understand the tradeoffs.
When should I replace my phone’s battery?
Consider replacing your phone’s battery if you notice any of the following signs of aging:
- Battery life falling below 50% of original capacity
- Phone dying quicker even when cool
- Need to charge more than once per day
- Battery runs hot while charging
- Swelling or distortion of battery
Lithium-ion batteries degrade over time. Heat accelerates wear. Plan on a replacement battery after 2-3 years for optimal performance.
Should I use a thick phone case if I live somewhere hot?
Thick plastic or leather cases can insulate your phone and retain more heat in hot environments. If overheating is an issue, use a minimal case instead.
Look for cases marketed as “slim”, “thermal”, or “cooling”. Cases with open sides or perforations can help prevent trapped heat buildup.
Remove any case periodically to allow maximum air circulation to hot phones. But still use a case for scratch protection if needed.
Can I fix overheating by rooting or jailbreaking my phone?
Rooting Android devices or jailbreaking iPhones does allow tweaking settings related to performance, cooling, and battery usage. This level of customization can potentially reduce overheating.
However, rooting and jailbreaking come with security tradeoffs. They also void manufacturer warranties. Only use advanced mods if you understand the risks and downsides involved.
Is it safe to keep using a phone that feels hot?
It’s generally not recommended to keep using a phone that feels excessively hot for prolonged periods. At best, performance will be throttled. At worst, components can be degraded or damaged.
Stop phone use if it feels uncomfortable to hold. Let it cool down completely before resuming normal operation. Persistent heat is a warning sign that requires attention.
Can I prevent overheating by adding a cooling fan?
Yes, attaching an external cooling fan can help lower phone temperatures by increasing airflow. Small USB/battery powered fans are affordable options.
Look for clip-on fans designed to point directly at your phone’s back or sides. Avoid fans that blow across the front screen to prevent dust buildup.
Fans provide limited cooling, so severe overheating requires other measures as well. But they can provide a useful assist with thermal management.
Conclusion
Overheating is a common smartphone issue with several potential causes. While occasional mild heating is normal, sustained high temperatures can degrade your phone’s performance and lifespan.
Be mindful of situations which cause excessive thermal buildup like gaming or charging on hot days. Proactively manage your phone’s temperature using cooling accessories, proper ventilation, and avoiding heat sources.
Immediately stop using and charge an overheated phone. Persistent high temperatures or physical changes require manufacturer support to inspect and repair your device.
Understanding the causes, effects, and solutions for overheating can help you maximize your phone’s capabilities and longevity through all conditions.