Learning Java: Celcius to Fahrenheit Conversion
double celciusInputs, fahrenheitInputs = celciusInputs = 0;

Variables declared and initialized this way are hard to read. Prefer:
double celciusInputs = 0;
double fahrenheitInputs = 0;



double celciusInputs, fahrenheitInputs = celciusInputs = 0;

The Inputs in the name signals to me that it is an array of values. It is not. Prefer celciusInputsSum and fahrenheitInputsSum


System.out.print(&quot;Enter Temp in Centigrade or &lt;= -100.0 to quit: &quot;);

Spell out Temp as temperature to avoid confusion. Centigrade should also be worded as &quot;Celsius&quot; to avoid confusion (even variable names use &quot;celsius&quot;, not &quot;centigrade&quot;)
Why is minimum allowed temperature -100.0 °C? Absolute zero is at -273.15 °C


input = in.nextDouble();

Error handling should be added. What do you want to do when user enters foobar as input?


double conversion = ((9.0/5.0) * input) + 32.0;

From this line alone, we do not know the units. Prefer fahrenheitConverted or similar


counter += 1;

Instead of summing the inputs, perhaps consider ArrayList to store the inputs. The sum can only go so far before celciusInputs and fahrenheitInputs overflow. It also provides more flexibility if you want to do other calculations (such as calculating mode and median, along with the mean/average)


celciusInputs /= counter;
fahrenheitInputs /= counter;


Doing it like this means the variable names no longer reflect its contents. Prefer using new variables like this: double celsiusInputAverage = celciusInputs / numInputs


public static void main(String[] args) {

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