How to check your iPhone's battery health and cycle count

Keeping tabs on your iPhone's battery health and charge cycle count is a smart way to gauge when a replacement might be needed. Apple provides built-in tools to surface this data, helping users avoid unexpected performance slowdowns and make informed decisions about repair or upgrade timing.

Your iPhone's battery degrades a little with every charge cycle, and over time that wear translates into reduced capacity and, potentially, throttled performance. Apple has built diagnostic tools directly into iOS that let users see exactly how much capacity their battery retains compared to when it was new, along with the number of full charge cycles it has accumulated.

Accessing this information requires just a few taps inside the Settings app, under the Battery section. Knowing your cycle count is particularly useful when buying a used iPhone, since a device with several hundred cycles already logged may need a battery swap sooner than expected — an expense worth factoring into the purchase price.

Every rechargeable lithium-ion battery has a finite lifespan measured in charge cycles — one cycle being the equivalent of draining and refilling 100 percent of capacity, even if that happens across multiple partial charges. Apple's own guidance suggests that an iPhone battery is designed to retain up to 80 percent of its original capacity after around 500 complete cycles under normal conditions.

Apple has gradually made it easier for users to access this data without needing third-party apps or connecting to a computer. Current versions of iOS surface battery health percentage directly in the Settings app, and more recent software updates have extended visibility to include the raw cycle count — a figure that was previously hidden or required workarounds to retrieve.

To find this information, users can navigate to Settings, then Battery, and finally Battery Health and Charging. The displayed maximum capacity percentage shows how the battery compares to its original specification, while the cycle count offers a more granular picture of cumulative wear.

Why it matters: battery health directly affects day-to-day experience. iPhones with significantly degraded batteries can trigger Apple's performance management system, which slows processor speeds to prevent unexpected shutdowns — something users may mistake for a hardware problem or a sign they need a new phone entirely. Regularly checking these metrics empowers owners to decide proactively whether a relatively inexpensive battery replacement could extend a device's useful life by a year or more.

This knowledge is equally valuable in the second-hand market. A used iPhone listed at an attractive price may look appealing until a quick battery health check reveals a cycle count in the high hundreds and capacity well below 80 percent, signaling that a replacement battery will likely be needed soon and adding hidden cost to the deal.