it takes quite a bit of time if you are charging with the phone ON.
i try to charge it in the morning when i can leave it OFF for a few hours.
i bought the extended battery -- but since i won't be able to use my Trident case with the extended battery, i decided to get the desk charger and one more OEM standard battery....since you can have a battery on the desk charger charging up all the time, and just switch batteries.
i love the phone.....this much power and capability needs a lot of battery!
i remember being unhappy with the last extended battery i had -- it made the phone so much more bulky and unpleasant to carry......learned my lesson.....gonna stick with the slim, stock OEM battery!