Slow iPhone? Here’s how to check the health of your battery

Is it time to replace your iPhone’s battery?

With all the fuss about old, depleted batteries slowing down your iPhones, it might be a good idea to at least check the health of your iPhone’s battery. To do this, you can use a free tool called coconutBattery, an app that digs into your iOS and Mac devices to tell you how old they are, and how strong your battery is compared to when it was new.


CoconutBattery is an Mac app that performs a single task — it checks the status of the battery in your Mac, or the battery of any iDevices connected to that Mac. To use it, you just plug your iPhone or iPad into your Mac, and make sure that it trusts the host computer (if you regularly sync your iPhone with your Mac, you can skip the “trust” step. If you don’t, then just follow along with the instructions that will appear on your Mac and iPhone’s screens).

Once connected, you’ll see a window something like this:

All you need to know about your iPhone battery in one place.

That’s the iOS page of the coconutBattery window, and it shows you several pieces of useful info. The top section is basic data about the connected iPhone (or iPad): dater of manufacture, OS version, device model, and the storage space currently used. For more details –serial number, ages in days, and the current kind of charger connected — click on the Device details… button.

Below that is the section we’re interested in: the battery details. Here you will see two bars, hopefully both green. The upper bar shows you the current charge level of the battery (similar to the percentage readout on the iPhone itself), along with the current charge, and the full possible charge capacity in milliAmp hours (mAh).

New vs. old

Below that is a bar showing the “design capacity” vs the current capacity. That is, it shows you how much charge your iPhone’s battery can hold today, vs how much it could hold when it left the factory (the “design capacity” is the official spec for you device — the actual capacity when new could be slightly over or under that number, but it is a good guide).

Thus, you can see just how weak your battery has become over the years. You can also see how many charge cycles the battery has been through.

Works on Mac batteries too

CoconutBattery also works on the Mac.

How to maximize your battery’s lifespan

There are several tips yo can follow to keep you battery healthy for as long as possible. Apple has a support page dedicated to just that, and it’s a great read if you want the truth about batteries from the source. After all, who would know better about battery life and health than Apple, a company obsessed with optimizing battery performance so it can make its devices ever smaller?

Check it out, and maybe you’ll be able to make your current iPhone last a little longer.

If you are running coconutBattery on a Mac with a battery i.e. a MacBook, then you can see this info for your Mac’s battery too. And you can also save the current data in order to keep a record of your batteries’ depletion over time. And finally, there’s a coconutBattery Plus upgrade to let you check iOS batteries wirelessly, and to unlock battery charge notifications, plus advanced viewers for Mac and iOS.