How to test battery on an iPhone

To test the battery on an iPhone, you can use the built-in battery health feature. Here's how to access it:

1. Open the Settings app on your iPhone.
2. Tap on Battery.
3. Tap on Battery Health.

On this screen, you'll see two important pieces of information: Maximum Capacity and Peak Performance Capability.

Maximum Capacity represents the maximum amount of charge your battery can hold compared to when it was new. Ideally, this number should be close to 100%. If it's significantly lower, it may be time to replace your battery.

Peak Performance Capability represents your phone's ability to handle high-performance tasks without shutting down unexpectedly. If your battery is experiencing issues, this number may be lower than 100%. You may also see a message here indicating that your iPhone has experienced an unexpected shutdown.

In addition to checking your battery health, there are several other ways to test and maintain the battery on your iPhone:

1. Reduce screen brightness: Lowering your screen brightness can help extend your battery life. You can adjust the brightness in the Control Center or in the Display & Brightness section of the Settings app.
2. Turn off unnecessary features: Turn off features like Wi-Fi, Bluetooth, and location services when you're not using them. You can also turn on Airplane Mode to disable all wireless features at once.
3. Close apps when not in use: Closing apps when you're not using them can help reduce power consumption and improve battery life.
4. Use low power mode: When your battery gets low, your iPhone may prompt you to turn on Low Power Mode. This feature reduces power consumption by disabling certain features and limiting background activity.
5. Check battery usage stats: Your iPhone has a built-in feature that allows you to see which apps are using the most battery power. To access this feature, go to Settings > Battery. Here, you can see which apps are using the most battery power over the last 24 hours or the last 10 days. Use this information to identify apps that are draining your battery and adjust your usage accordingly.
6. Use optimized battery charging: If you have an iPhone running iOS 13 or later, you can enable the optimized battery charging feature. This feature learns your daily charging routine and waits to finish charging past 80% until you need to use your phone. This can help extend your battery life by reducing the amount of time your battery spends at 100%.
7. Keep your iPhone updated: Make sure your iPhone is running the latest software updates. These updates often include performance improvements and bug fixes that can help improve battery life.
8. Use low-power mode: When your battery gets low, you can turn on Low Power Mode to reduce power consumption. This feature disables certain features and limits background activity to help extend your battery life.
9. Calibrate your battery: Over time, your iPhone's battery may lose accuracy in reporting its remaining charge. Calibrating your battery can help fix this issue and improve the accuracy of your battery level readings. To calibrate your battery, fully charge your phone, then use it until it shuts off due to low battery. Charge your phone to 100% again, and repeat the process once or twice.
10. Use Wi-Fi instead of cellular data: When possible, connect to Wi-Fi instead of using cellular data. This can help reduce power consumption and extend your phone's battery life.
11. Adjust screen timeout: Shortening the amount of time your screen stays on can help reduce power consumption. You can adjust the screen timeout in the Display & Brightness section of the Settings app.
12. Turn off automatic downloads: By default, your iPhone may automatically download app updates, music, and other content in the background. Turning off automatic downloads can help reduce power consumption and improve battery life. You can adjust these settings in the App Store or iTunes & App Store section of the Settings app.
13. Turn off Raise to Wake: If you have an iPhone with Raise to Wake enabled, your phone will turn on the screen when you pick it up. This feature can be convenient, but it can also drain your battery. To turn off Raise to Wake, go to Settings > Display & Brightness and toggle off the Raise to Wake option.
14. Keep your phone cool: High temperatures can shorten your battery life and damage your phone's components. Avoid exposing your phone to direct sunlight, and keep it in a cool, dry place whenever possible.

By following these tips and testing your battery regularly, you can help ensure that your iPhone lasts as long as possible between charges.