What the fuck? in swedish

¯\(°_o)/¯ how do i said 'what the fuck' in swedish?

my guess is 'vad knullen' but i dunno if that's right

I wanna make a pedantic list:
Swedish -> Literally -> Meaning
"Vad i helvete?" -> "What in hell?" -> "What the hell?"
"Vad fan?" (Otherwise not proper grammar.) -> "What, devil?" -> "What the devil?" or "What the hell?"
"Vad tusan?" (Otherwise not proper grammar.) -> "What the thousand?" -> "What the heck?"
"Vadfalls?" (Otherwise not proper grammar, probably not even a proper word.) -> "What-falls?" -> "How do you mean?"
"Vad i helvete", "Va(d) fan" and "Vad tusan" can be combined with a sentence, like so:
"Vad i helvete gör du med min lilla-syster?!" -> "What the hell are you doing with my little sister?!"