How many watts is a 2A fast charger?
How many watts is a 2A fast charger? 5V 2A: Similarly 5V 2A charger is a 10W charger.
Is 2A or 10a better for charging?
If you will be monitoring the charge actively, you can punch up the 10A rate. If you will be walking away from it for hours or days, select 2A and that will better approximate the trickle charging it should get when full, so you will do less damage.
Is fast charging better 2A or 3A?
smartphones takes only the power it needs or handles upto. so you wont see any difference between 3A charger and 2A charger if your phone can support upto 5V 2A charging. But if your phone can take 3A of higher, You will find 3A charger faster than 2A charger As it takes more power available to charge the battery.