I want to say "what the hell", "what the f***", or "what the heck" in Spanish and have come across the following translations:
¡Qué mierda!
¡Qué demonios!
Which of these is the most natural translation to convey what I am trying to say? Is there yet another translation what is used more than the above two? Please mention your country so that one can understand what region your response pertains to.