How to calculate the voltage of Mkr zero

How to calculate the voltage of Mkr zero?

How 5V/1024 = 0.004882814V ?
I have tried it many times and I have got 5/1024 =0.0048828125

Get real.
So you seriously expect eight places of decimals?

To calculate the voltage of Mkr zero

int sensorValue = analogRead(A0);
float outvoltage = sensorValue * (5.0 / 1023.0);
or
int sensorValue = analogRead(A0);
float outvoltage = sensorValue * (3.3/ 4095);
Which one is correct?

Neither, obviously.

They would be 3.3V divided by 1024 and 4096