@jeylites You may change R1 and R2 and you don't destroy (A0).

An other way is to change the multiplicator (0.003363075) in the formula:
float batteryV = sensorValue * 0.003363075;

How can I present the value in Voltage (for example 3.06 V)? I don't like the "Battery monitor".

I have got the multiple temperature meter (DHT + Dallas) working very well. Would be nice to have battery level in volts also.

Cheers!