How hot is too hot for a phone?

by
How hot is too hot for a phone

Modern smartphones, such as iPhones and Android devices, are incredible feats of engineering. Packed into small and sleek devices are advanced processors, high-res displays, wireless chips, cameras and more. But with all these components working hard in tight quarters to deliver peak performance, today’s phones can get hot, especially when pushed to their limits. Just how hot is too hot for a phone? We’ll explore the factors that contribute to phone heat, look at safe and dangerous temperature thresholds and provide tips for keeping your device cool.

What causes a phone to get hot?

Several factors can contribute to a phone heating up during use:

  • Processor-intensive tasks like gaming, streaming video or navigation cause the chip to work overtime and heat up.
  • Using features that require wireless radios like mobile data, WiFi, Bluetooth or GPS generates additional heat.
  • Charging the battery adds heat as electricity flows into the device.
  • Extended exposure to direct sunlight, especially in hot climates or in cars.
  • Older phones may run warmer due to battery age or dust buildup in vents blocking cooling.

It’s normal for phones to get somewhat warm with typical use. But excessive heat can impact performance and battery life. It can also make the device uncomfortable to hold.

What temperatures are considered normal or dangerous for phones?

Most phones are designed to operate at ambient temperatures between 32°F to 95°F (0°C to 35°C). Here are some general guidelines on phone temperatures:

  • Up to 95°F (35°C): Normal range during active use.
  • 95°F to 105°F (35°C to 40°C): Gets uncomfortably warm but not dangerous if exposure is brief.
  • 105°F to 120°F (40°C to 49°C): Very hot and sustained operation not recommended.
  • 122°F (50°C) and up: Extreme temperatures that can damage the battery and other components.

To put this in perspective, the maximum recorded temperature on Earth is 134°F (56.7°C) in Death Valley, California. No phone could survive that kind of heat for long.

Signs your phone is excessively hot

Here are some signs that your phone is overheating and action may be required:

  • It feels very hot when holding it.
  • The display looks dimmer than usual.
  • Apps are laggy or unresponsive.
  • The phone turns itself off or reboots on its own.
  • You get warnings that the device needs to cool down before use.
  • There are suspicious smells coming from the device.

Sustained overheating can eventually lead to permanent hardware damage. The most vulnerable components are the battery, display and processor.

Tips to prevent and manage overheating

Here are some tips to keep your phone running cooler:

  • Don’t leave devices in direct sunlight or enclosed spaces like cars where temperatures can skyrocket.
  • Avoid processor-intensive activities like gaming or videos during charging.
  • Disable background app refresh and location services when not needed.
  • Close recently used apps not currently in use.
  • Add a phone case to provide insulation and dissipate heat.
  • Keep the phone away from soft surfaces that can trap heat like beds or sofas.
  • Avoid charging cases or accessories that generate additional heat.
  • Use air conditioning or point a fan at the device.
  • Consider an external cooling fan attachment.
  • If overheated, remove the case and shut down the phone until it cools off.

Should you be worried about 5G and phone heat?

Early 5G networks led to some overheating concerns due to the combination of new 5G modems and coverage limitations requiring phones to use more power to maintain signals. However, over the past two years, 5G technology and coverage has improved significantly:

  • New modems like the Snapdragon X65 are built on advanced 5nm process nodes, delivering dramatically improved power efficiency.
  • Carriers have expanded 5G networks with additional spectrum bands for better coverage. 5G signals go farther and penetrate buildings better, meaning phones don’t have to work as hard to maintain connections.
  • Smartphone designs have continued to advance, with better antennas, strategic use of graphite sheets to dissipate heat and vapor chambers for cooling critical components.

As a result, overheating concerns have diminished considerably relative to early 5G devices. Any impacts are typically only noticeable during very heavy usage. Furthermore, phones intelligently manage connections, defaulting back to 4G LTE to conserve battery life if 5G is not needed for the task at hand.

How phone materials impact heat dissipation

A phone’s external case and frame materials can influence how heat dissipates. Materials like aluminum and magnesium are conductive and help dissipate heat away from internal components. Plastics insulate and keep heat contained within the chassis. Here’s how common materials compare:

Material Thermal Conductivity Heat Dissipation Ability
Aluminum High Best heat dissipation
Magnesium High Excellent heat dissipation
Glass Low Minimal heat dissipation
Plastic/Polycarbonate Very Low Worst heat dissipation, traps heat

The tradeoff is that metals scratch more easily compared to ultra-strong glass or plastic. Phone designs aim to balance durability, looks and thermal characteristics.

How phone case materials impact heat

Phone case materials also influence heat buildup and dissipation:

  • Plastic/Silicone cases – Made of thermal insulators resulting in higher operating temps. But provides protection from drops.
  • Wood cases – Natural insulator that retains heat. Appealing but not ideal for heat.
  • Leather cases – Also heat insulating and less breathable. Better for style than cooling.
  • Metal cases – Made of conductive metals like aluminum alloy that readily shed heat. But less protection from drops.
  • Mesh/breathable cases – Promote air circulation and better cooling. Less protective but great for heat.

Ideally, look for a case advertised as “cooling” or “ventilated” to prevent overheating. Or quicky remove your case if heat becomes excessive.

How screen technology impacts thermal performance

Displays generate substantial heat due to the backlight and digitizer components. Screen technology has improved thermal characteristics:

  • LCD screens – Require backlight and can run hotter. Primarily used on budget devices.
  • OLED screens – Self-lit pixels, no backlight, operate cooler. Used on most flagship phones.
  • LTPO OLED – Further reduces power for screen. Latest in OLED tech for optimal efficiency.

So OLED and LTPO screens found in premium phones like iPhone 13 Pro and Galaxy S22 Ultra run significantly cooler than cheaper LCD screens.

Gaming and processor heat

Resource-intensive 3D games push smartphones to the limit. Sustained gaming heats up the processor, especially at higher frame rates with fancy graphics enabled:

  • Casual games like Candy Crush have minimal impact.
  • 2D games like Angry Birds are light to moderate loads.
  • 3D games like Call of Duty heavily tax the processor and GPU.
  • Increasing graphics quality and frame rates further heats up the SOC.

Consider capping frame rates at 30 fps, using a phone cooler, and taking periodic breaks if playing GPU-intensive games for long periods.

How battery age and health impact heat

As phone batteries chemically age through repeated charging cycles, their ability to hold a charge decreases. Running an older battery requires more power draw to achieve the same performance, resulting in extra heat. Batteries also heat up faster when damaged or punctured. Check battery health and consider replacing batteries older than 2 years to maintain optimal thermal performance.

Does wireless charging heat up phones?

Wireless charging generates noticeably more heat compared to wired charging methods. However, most phones use built-in protections against excessive wireless charging heat:

  • Phones with glass backs allow for better heat dissipation.
  • Chargers activate cooling fans once a temperature threshold is reached.
  • Charging speed is throttled once high temps are detected.
  • Notifications warn the user if heat exceeds safe limits.

While wireless charging tends to run hotter, most phones are designed to handle it without damage. But phones may activate warnings or charging stops if overheating occurs.

Does fast charging increase phone heat?

Higher wattage fast charging does produce more heat compared to slower 5W chargers. However, precautions are taken to keep temps in check:

  • Fast charging only activates when battery level is low, minimizing heat.
  • As charge reaches around 70-80%, charging wattage tapers down significantly.
  • Once fully charged, charging stops entirely until battery depletes again.
  • Fast charging produces temporary heat spikes but not continuous high heat.

Occasional fast charging is safe for most phones. But sustained wireless or fast charging while gaming or in hot environments can reach concerning temps.

How weather and climate impacts phone heat

Ambient environmental temperatures greatly influence phone operating temperatures. Some weather conditions that can heat up phones include:

  • Direct sunlight – Especially in cars or on dark surfaces.
  • High heat and humidity – Stifles convection cooling in hot climates.
  • Intense cold – Phones work harder to stay operational.
  • Wind / AC Vent direction – Can chill phones below operating range.

Avoid leaving phones in cars on hot days or direct sunlight for prolonged periods. Ideal ambient temperature range is around 70°F to 80°F (21°C to 27°C).

Warning signs of damage from overheating

Some physical signs of heat damage in phones include:

  • Warped or discolored casing
  • Separation of glued seams and joints
  • Melting of protective cases
  • Discoloration or distortion of screens
  • Separation of display glass from frame
  • Swelling or puncturing of battery
  • Scuffs or burnt spots on ports
  • Bubbled, cracked or peeled paint and coatings

If you observe any of these warning signs, discontinue use and seek repair. Damage from extreme overheating is not covered under warranty.

Maximum safe operating temperature by phone model

Here are approximate maximum safe operating temperatures for popular phone models under sustained maximum load. Temperatures above this range risk hardware damage.

Phone Model Max Safe Temperature
iPhone 14 Pro Max 122°F / 50°C
iPhone 13 Pro 122°F / 50°C
iPhone 12 Pro Max 113°F / 45°C
Samsung Galaxy S22 Ultra 113°F / 45°C
Samsung Galaxy S21 Ultra 113°F / 45°C
Google Pixel 7 Pro 122°F / 50°C
Google Pixel 6 Pro 113°F / 45°C

Actual thresholds vary slightly by specific unit and operating conditions. But sustained temps beyond 122°F (50°C) risk permanent component or battery damage.

Tips for monitoring phone temperature

To keep tabs on your phone’s temperature, try these tips:

  • Use an app like CPU Thermometer to view real-time temp info.
  • Notice when phone feels hot to the touch during use.
  • Watch for warning messages about shutting down due to heat.
  • Consider a physical infrared thermometer to scan surface temps.
  • Monitor battery temp readings using diagnostic tools.

Routinely checking your phone’s temperature equips you to take action before permanent damage occurs.

Conclusion

Today’s smartphones pack immense power into compact form factors, so some heat is inevitable. But sustained temperatures beyond 113°F – 122°F (45°C – 50°C) can damage sensitive components like displays, processors and batteries. While occasional peaks are usually harmless, chronic overheating degrades hardware over time. Being mindful of conditions that generate excessive heat allows you to take proactive cooling measures. With some awareness and care, your phone should operate for years at hot-but-safe temperatures.