A:Answer I don't know, because I've never run it down. I have used it all day long at conferences, running the syllabus and an app or two, 8 to 5, and still have about 50% left. I am very pleased with the long battery life, the bright and sharp images, and everything about it. At the end of the day, I put it on the charger. Seriously, I've never gotten it close to depleted.