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How To Calibrate iPhone Battery for an Accurate Percentage

iPhone battery iconThe top right corner of your iPhone screen shows just how much juice is left in the battery. You’ll know that you need to recharge when the icon shows that the battery is running dry, or when a warning pops up. Fun fact: iOS uses statistics to determine battery life in relation to your activities. If your battery percentage is jumpy, you need to calibrate your iPhone battery – or, to be more precise – recalibrate the iPhone battery statistics.

Why you should calibrate your iPhone battery

Ever noticed how your iPhone battery percentage becomes unreliable or jumpy, especially during the last few hours of usage before it runs dry? If your iPhone tends to switch itself off, it might be due to inaccurate estimations. A special type of software power controller takes into account various variables and tries its best to anticipate your actions. This result is then displayed in the battery charge indicator you see in your status bar. Although Apple did a great job in terms of energy management, the system can get confused after a period of usage.

Calibrating the iPhone battery is another way of saying that we’ll try and tell the power control software to reset part of the statistics and rediscover how we use our phones. The end result: More accurate battery percentages and battery indicators, no more unexpected shutdowns.

iPhone battery warning

How to calibrate iPhone battery without any extra tools

Fully discharge > Fully charge > Repeat 1x

Calibrating the iPhone battery, or rather its control mechanisms, is accomplished by fully discharging the iPhone through regular use. Streaming a bunch of videos on Netflix and YouTube with your brightness cranked up all the way will accomplish a discharge pretty quickly. Any kind of regular usage does the job, too. Simply continue using the phone until it switches itself off after the two battery warnings are triggered. Close and ignore the warnings as they appear.

After the automatic shutdown, take your wall socket charger and connect your iPhone to a power outlet. Let it charge up completely without using it and wait for it to reach 100 percent (fully charged). Give it one or two extra hours after that, just to make sure that the battery is really filled to the brim.

Now unlock your iPhone and perform a “warm restart” by holding the two hardware buttons until you see the Apple logo. Then use your iPhone until it fully discharges again, repeating the cycle once more (fully discharge, then fully recharge and reboot). This will give you the most accurate battery readings and recalibrate the battery.