You cannot know if your AirPods are charging, but it's easy to tell if they are fully charged or are running low using the LED indicator on the AirPods case. When you open the AirPods case, a green light means fully charged, and amber means less than one full charge remains. If your AirPods are in the case, the light shows the charge status of your AirPods, but if your AirPods aren't in the case, the light shows the status of your case.