It takes me abut 3 hours to get 100% from 0%, sometimes longer because I us the iPad while it's charging
A quick couple questions for you:
1. Are you charging it through a computer's USB port?
2. Are you using an iPhone or iPod touch's charging adapter instead of the larger, more powerful charging unit that came with the iPad?
3. Have you recently used any travel voltage/amperage adapters with your iPad?
The iPad will still charge via USB or with chargers designed for the iPhone/iPod, however, the wattage is twice that compared to the one included with an iPhone, and has a higher amperage rating (2.1A). USB ports also work, but charge at a slower rate than using the supplied charger.
If you using the charger that came with your iPad, and are noticing longer than usual charging times, make an appointment with your nearest Apple store's Genius Bar, where they can check it for you. Make sure you do one last sync with your computer before going, as they may replace your iPad under warranty if it indeed is not taking a charge properly.
After my wife traveled to Europe with our iPad, upon returning to the US, we noticed that our ipad was intermittently taking a charge and/or charging very slowly - so we made an appt at our closest Apple store's Genius bar, and upon verifying the charging problem, replaced my iPad with a new one.
I cannot tell you what they will do for you when you go and see them, as it is up to the techs that look at your device, but they have the tools and the knowhow to diagnose and troubleshoot Apple products better than anyone.
i charge through the mains, and i am sure my ipad didnt come with a charger, just a usb cable, do you have a picture of what charger you are talking about so i can be certain.
This is the charger that is supplied in all US sold iPad boxes:
Apple said:Charging Tips
The quickest way to charge your iPad is with the included 10W USB Power Adapter. iPad will also charge, although more slowly, when attached to a computer with a high-power USB port (many recent Mac computers) or with an iPhone Power Adapter.
When attached to a computer via a standard USB port (most PCs or older Mac computers) iPad will charge, but only when it's in sleep mode. Make sure your computer is on while charging iPad via USB. If iPad is connected to a computer that’s turned off or is in sleep or standby mode, the iPad battery will continue to drain.
Apple iPad 10W USB Power Adapter - Apple Store (U.S.)