Long enough for me to use at an all-day conference without worrying about recharging. I'd estimate somewhere between 6 and 8 hours. It's hard to say because I'

Long enough for me to use at an all-day conference without worrying about recharging. I'd estimate somewhere between 6 and 8 hours. It's hard to say because I've never actually run it down fully, but it still estimates another couple hours' worth after I've been using it for 5 hours or so. Estimates should be taken with a grain of salt, but for comparison, that's more than I get on my larger laptop, and comparable to what I get on my Macbook Air.