function CelsiusToFahrenheit(Value: double): double; 
begin 
  result := Value * 1.8 + 32; 
end; 
 
function CelsiusToKelvin(Value: double): double; 
begin 
  result := Value + 273.15; 
end; 
 
function CelsiusToReaumur(Value: double): double; 
begin 
  Result := Value * 0.8; 
end; 
  
function KelvinToCelsius(Value: double): double; 
begin 
  result := Value - 273.15; 
end; 
 
function KelvinToFahrenheit(Value: double): double; 
begin 
  result := Value * 1.8 - 459.67; 
end; 
 
function KelvinToReaumur(Value: double): double; 
begin 
  result := (Value - 273.15) * 0.8; 
end; 
  
function FahrenheitToCelsius(Value: double): double; 
begin 
  result := (Value - 32) / 1.8; 
end; 
 
function FahrenheitToKelvin(Value: double): double; 
begin 
  result := (Value + 459.67) / 1.8; 
end; 
 
function FahrenheitToReaumur(Value: double): double; 
begin 
  result := (Value - 32) / 2.25; 
end; 
  
function ReaumurToCelsius(Value: double): double; 
begin 
  result := Value * 1.25; 
end; 
 
function ReaumurToFahrenheit(Value: double): double; 
begin 
  result := Value * 2.25 + 32; 
end; 
 
function ReaumurToKelvin(Value: double): double; 
begin 
  result := Value * 1.25 + 273.15; 
end; 
 
 
// Beispielaufruf 
 
procedure TForm1.Button1Click(Sender: TObject); 
begin 
  showmessage(FormatFloat('#,##0.0 °C', FahrenheitToCelsius(212.0))); 
end;