Skip to Content

Is it Ok to Fully Charge iPhone?

As an iPhone owner, I’ve been frustrated trying to figure out the best way to charge my phone. After much research and experimentation, I’m here to share what I’ve learned and provide some solutions on the question: is it ok to fully charge an iPhone? In this blog post, I’ll discuss the pros and cons of fully charging an iPhone, as well as the best practices for charging and maintaining your device.

So is it okay to fully charge an iPhone? The answer is no; it’s not. Full charging shortens the lifespan of the battery. 

Full Charging IssuesFully charging an iPhone shortens the lifespan of the battery due to the stress on the electrodes during the charging process.
Best Charging PracticesKeep your iPhone’s battery level between 20% and 80%, activate Optimized Charging Mode, and charge your iPhone periodically.
Activating Optimized Charging ModeGo to Settings > Battery > Battery Health, and turn on Optimized Battery Charging. Also, activate Significant Locations under Privacy and Security > Location Services > System Services > System Customization.
Charge PeriodicallyCharging your iPhone more often actually helps extend the battery’s lifespan by keeping it within a healthy range.
Exception for Full ChargingFull charging is only recommended when recalibrating a malfunctioning battery. To recalibrate the battery, drain it to 0%, then charge it to 100% without interruptions, and reboot the iPhone. If it’s not at 100% after rebooting, continue charging until it reaches 100%. This should recalibrate the battery, but keep in mind it still reduces the battery life.
ProsOptimized charging mode and charging periodically help extend the battery’s lifespan.
ConsFull charging shortens the battery’s lifespan, and recalibrating the battery reduces its overall life.
Final ThoughtsAvoid letting your iPhone’s battery level fall below 20% and unplug it when it’s between 80-100%. This keeps your iPhone convenient to use while optimizing the battery’s lifespan.

Why Is It Not Ok to Fully Charge an iPhone?

Lithium-ion batteries like the one in an iPhone work by transporting charge carriers from one electrode to another when it’s being charged. In this case, these carriers are lithium ions, hence the name that the batteries have.

As they function by passing ions from one electrode to another, lithium-ion batteries slowly corrode over time as they’re charged over and over again. They’ll eventually lose charge capacity and use up power a bit faster as the electrodes are stressed in the process. 

How Do I Charge My iPhone Right?

To delay the inevitable senility of your battery, you should never fully discharge or charge your iPhone. The lower limit is 20%, as the iPhone will remind you to charge it when it reaches this level.

As for the highest battery percentage, it’s best for it to be around 80% to avoid stressing the electrodes too much. To accomplish this on your iPhone, you can use the optimized charging mode. 

1. Activate Optimized Charging Mode

Apple has implemented an optimized charging mode ever since the iOS 13 software update. When activated, this feature stops your iPhone from charging over 80% in some situations, thereby optimizing your battery life. 

It also slows down your charging, thereby keeping your battery in the “sweet spot” between 20% and 80% for longer.

It’s turned on by default when you first get an iPhone with iOS 13, or when you update an older iPhone. To make sure that it’s turned on, you’ll have to check it in the settings. 

  1. Go to Settings
  2. Tap Battery
  3. Tap Battery Health
  4. Turn on Optimized Battery Charging

However, the optimized charging mode isn’t always engaged. It takes time for it to take full effect as it’s an algorithm that learns your charging routine and activates when it thinks that you’re going to charge for a long time.

It’s also dependent on location marking. It most often engages when you’re at the workplace or at home. Usually, it won’t work when you’re traveling.

To make maximum use of the optimized charging mode, you’ll have to activate some location settings:

  1. Go to Settings
  2. Select Privacy and Security
  3. Tap Location Services
  4. Go to System Services
  5. Select System Customization
  6. Turn on Significant Locations

Once Significant Locations is turned on, Optimized Charging Mode will be active wherever you are, even if you’re traveling.

2. Charge Periodically

Contrary to popular belief, lithium-ion batteries don’t degrade faster when they’re charged more often. In fact, this actually lengthens the battery’s lifespan.

This is because both extremes of zero and 100% are stressful to the battery’s electrodes. Keeping it in between is healthy, as shown by Apple’s advice to keep iPhones half-charged when they’re stored for the long term.

Is There Any Time When It’s Okay to Fully Charge an iPhone?

There’s actually a single exception to the rule that your battery should never be charged to its full capacity. This is when you have to reset the battery when it malfunctions.

To be specific, this is when:

  • The battery indicator stays unusually long in a certain percentage, and then suddenly goes down in an instant.
  • The battery mysteriously dies even though the indicator shows plenty of charge left.

This happens because while the electrodes of the battery degrade, the digital chip that projects the reading doesn’t. They become inconsistent with each other over time, and have to be reset.

In this case, in order to recalibrate the battery, you’ll have to:

  1. Get it down to zero percent, without charging it anytime in between. Do this until it turns off by itself.
  2. Plug the charger and wait until it reaches 100%.
  3. Once it does so, remove the charger and reactivate the iPhone
  4. If it’s not at 100% when you reboot it, keep charging until it reaches 100%.
  5. Once it’s at 100%, the battery setting has been recalibrated.

Keep in mind that this still reduces your battery life. However, doing this stops the battery from malfunctioning. 


  • Optimized charging mode helps keep your battery in the “sweet spot” between 20% and 80% for longer.
  • Charging periodically helps extend the lifespan of the battery.


  • Full charging shortens the lifespan of the battery.
  • Recalibrating the battery reduces the battery life.

Final Thoughts

Read more: iPhone randomly opening apps

Is it ok to fully charge an iPhone? Only when recalibrating your battery, but in all other times it’s not. 

While it’s generally suggested to keep your battery level between 20-80%, it’s simply inconvenient. Instead, it’s easier to just not let it fall below 20%, and unplug it when it’s somewhere between 80-100%. It’s not advisable for it to be at 100% for a long time.

This way, the iPhone you have is still convenient to use, while the battery’s lifespan is optimized.

Read more: is the iPhone 4k?