With a Samsung Galaxy S21 fast charger, you can charge your S21, S21 Plus, or S21 Ultra extra quickly. The original Samsung 25W Power Delivery fast charger fully charges your battery in just over an hour. If you have a Power Delivery or Quick Charge charger with less than 25 watts of power, that takes about 1.5 hours. That is still about twice as fast compared to a charger without fast charging. Chargers with a higher wattage won't damage your battery, but also won't charge your S21 extra quickly. A charger isn't included with the S21, only a USB-C fast charging cable. Combine it with a separate USB-C charger or choose a charger with cable if you want an extra one.