Use Your iPhone
The quickest way to check your battery level is via your iPhone. Take your AirPods case and open the lid. Bring it close to your iPhone, and a window should appear with the battery levels for the charging case and the AirPod earbuds. If the window does not appear, make sure you have Bluetooth turned on, and the AirPods are connected to your phone. You also need to have both AirPods in the case.