Power for Multiple Servos

I want to control 3 or 4 servos on an Arduino Uno, on 3 or 4 pins. Each servo is 4.8-6V...and I was just wondering how many voltages is needed for my batteries?

6V. Connect to power seperately from Arduino power. Grounds must be connected.
How many amps is a different question, dependent on the servos selected.

A rough guide is 1A minimum per servo that is active simultaneously - the peak current tends only to
be drawn when moving, so 4 servos that only move one at a time might be OK with 1 to 2A supply, but all move
together and 5A is a better estimate. It all depends. Most servos don't care if the supply is briefly overloaded,
the voltage will drop for a bit.

The Arduino does care, hence the advice to power it separately.

Typical servo power setup.