Use the cast. When writing code, correctness and maintainability are both important. While both choices may give you the correct answer, only one is obviously "i want to cast an int to a double". The other is "why is this number being multiplied by 1.0? this looks useless. oh, it's an int, so this makes it a double", which is useless cognitive load that you impose on the future reader of the code (which might be you in 3 months wondering what 3 months younger you was thinking when they wrote that).