How hot can a phone safely get?

Get to Know Your Phone’s Heat Limits

In 2016, Samsung received 92 reports of batteries overheating in the U.S., including 26 reports of burns and 55 reports of property damage, according to a Statista report. Phone overheating can clearly pose risks, but most of the time it’s harmless. Understanding when phone heat is normal or problematic can help you keep your device safe.

Normal Phone Operating Temperatures

During normal use, the battery temperature in a phone typically ranges between 25-35°C (77-95°F). This includes light activities like browsing the web, checking email, streaming music, and sending messages (source). The CPU temperature also hovers around 30-40°C (86-104°F) for routine tasks according to tests by OnePlus users (source). For more demanding activities like gaming or using GPS navigation, temperatures may reach up to 40°C (104°F) which is still considered normal and safe.

The outer shell or body of the phone where users hold the device tends to remain cooler, around 30-35°C (86-95°F). This is because the battery and processor are deeper inside the phone. However, the temperature can increase depending on usage and if the phone is in direct sunlight.

In general, fluctuations between 25-40°C (77-104°F) are typical for a phone’s battery, CPU, and outer body during regular operation. As long as the phone is not exceeding 40°C for extended periods, these temperatures are not a cause for concern.

Factors That Increase Phone Heat

There are several common factors that can cause a phone to get hotter than usual:

  • Using processor-intensive apps and features like 3D gaming, video streaming, video calling, or using the camera for long periods of time can make the phone work harder and heat up more quickly (1).
  • High screen brightness levels strain the battery and CPU leading to extra heat generation (2).
  • Using GPS navigation apps that constantly access the GPS sensor can cause the phone to get warmer (3).
  • Downloading large files, performing system updates, or syncing huge amounts of data can make the phone work overtime and heat up (1).
  • Leaving the phone charging for extended periods after it’s fully charged causes the battery to work harder and get hot (2).
  • Using fast charging increases heat compared to standard charging (3).
  • Direct sunlight, hot cars, and other warm environments can all raise the phone’s ambient operating temperature (2).




Maximum Safe Temperature Thresholds

The maximum safe operating temperature for lithium-ion batteries in phones is typically between 32°C and 45°C (90°F to 113°F), according to this XDA forum discussion. Once a lithium-ion battery exceeds 45°C, there is a risk of the electrolyte inside breaking down, which can lead to thermal runaway and potential explosions or fire.

Phone CPUs tend to have maximum operating temperatures around 60-80°C (140-176°F) before they will automatically throttle performance or shut down to prevent damage, according to this Quora thread. However, sustained temperatures above 45°C can degrade the CPU over time.

Many modern phones will show warnings if the internal temperature approaches the maximum safe threshold, around 60°C for the battery and 80°C for the CPU. Exceeding these temperatures repeatedly can pose risks of physical damage to components.

Signs of Overheating

There are several signs that indicate a phone may be overheating. According to Asurion (source), some common symptoms include:

  • Warm or hot casing – If the phone feels abnormally warm or hot to the touch, it could be a sign of overheating.
  • Dimming screen – To reduce power consumption and heat buildup, an overheating phone may dim the screen brightness.
  • Slowing performance – Throttling, laggy response times, and unexpected shutdowns can occur as the phone tries to cool itself down.
  • Battery draining faster – Excessive heat causes the battery to discharge faster.
  • Warning messages – Pop-up notifications about high temperature or auto-shutoff to prevent damage.
  • Random restarts – An overheated phone may spontaneously reboot as a protective measure.

According to DAndre Electronics (source), noticeable warmth around the battery, back cover, or display are also potential overheating indicators. Being aware of these symptoms can prevent further device damage.

Risks of Overheating

Sustained high temperatures can cause permanent damage to a phone. According to PCMag, the most vulnerable components are the battery and display. Excessive heat causes the battery to degrade faster, resulting in poorer battery life and potential swelling or explosion. It can also damage the display, causing discoloration or flickering. The CPU and other internal components are also at risk in extreme overheating situations. They may become damaged or desoldered from the logic board.

Letting a phone get too hot on a regular basis increases the chances of permanent damage over time. According to Asurion, sustained temperatures above 113°F (45°C) can fry circuits and melt internal components. Allowing the phone to get this hot even once significantly raises the risk of immediate failure. It’s important to be proactive and take steps to cool down an overheating phone to prevent long-term damage.

How to Cool a Phone

If your phone feels hot to the touch, there are several steps you can take to help cool it down:

  • Remove any phone case, as cases can trap heat and prevent cooling. Let the bare phone air out.
  • Turn off CPU-intensive features like Bluetooth, GPS, and mobile data when not needed. These can generate excess heat.
  • Exit any resource-heavy apps, games, or streaming video that may be causing overheating.
  • Enable battery saver mode or airplane mode to limit activity.
  • Use a cooling app that clears unnecessary background processes and stops runaway apps.
  • Turn down screen brightness to reduce energy usage and heat.
  • Power off and let sit to dissipate heat. Do not use or charge until fully cooled.
  • Point a fan directly at the phone to enhance passive cooling.
  • Place the warm phone on a cool surface like a table or tile floor.

If overheating persists even after trying these steps, your phone may need servicing. But in most cases, simply limiting the phone’s workload and allowing passive cooling time can bring temperatures back down to normal.

When to Be Concerned

In most cases, overheating is not a major issue and can be resolved by cooling your phone down. However, excessive or recurring overheating may indicate an underlying problem that needs attention.

You should be concerned if your phone overheats frequently, even when you are not using it heavily. Frequent overheating can degrade the battery faster over time. It can also damage other components like the CPU or display.

Signs that overheating may be linked to a hardware issue include the phone feeling abnormally hot, even when idle, or the overheating recurring after rebooting and removing apps. The phone may also feel hot in specific areas, like above the battery.

If you notice these patterns, it’s a good idea to back up your data and have the phone inspected by the manufacturer. Persistent overheating can mean issues like a swollen battery, degraded CPU, or motherboard failure.

Getting overheating issues checked out promptly can help prevent permanent damage. It’s better to be safe than sorry when your phone seems to be overheating beyond normal levels.

Preventing Overheating

There are several proactive steps you can take to help keep your phone cool and prevent overheating during normal use:

– Don’t use a case, as cases can trap heat. If you must use a case, choose one made of thin, breathable material. Avoid thick cases made of materials like silicone rubber (cite:

– Avoid extended direct sun exposure, don’t leave your phone sitting in the sun (cite:

– Don’t use your phone while it’s charging, as charging generates heat. Only use your phone while charging when necessary.

– Close any resource-intensive apps when not in use, as they can raise the phone’s temperature in the background.

– Turn down screen brightness, as higher brightness levels use more battery power and generate more heat.

– Switch your phone to airplane mode if you don’t need internet access, as cellular data transfer generates heat.

– Avoid playing graphics-intensive games for long periods, as 3D gaming causes significant processor usage and heat buildup.

– Keep your phone away from other hot objects and out of confined, poorly-ventilated spaces where heat can accumulate.

– Clean out your phone’s charging port regularly to avoid lint and dust buildup that can impact heat dissipation.


Overall, while modern smartphones are designed to withstand normal heat during operation, extended exposure to temperatures over 95°F can potentially damage phones and pose risks to users. The safest operating temperature range is between 32-95°F. Signs your phone may be overheating include the device feeling hot to the touch, lagging or freezing, the display dimming, apps crashing frequently, and warning messages popping up. To keep your phone operating safely and prevent dangerous overheating, avoid direct sunlight exposure, don’t cover the device, close resource-heavy apps when not in use, keep the phone properly ventilated, and avoid wireless charging if the phone feels hot.

By monitoring your phone for signs of excessive heat and making a few adjustments to prevent overheating, you can ensure safe operation and extend the usable lifespan of your device.