In all the world, Šťastný (Šťastný 
) is an extremely rare unknown gender first name. Much more frequently, Šťastný is the last name as well as the forename.
Dan, Peter, Radim, Radek, Radko, Rosťa, Roman, Robin, René, Danny, David, Dawid, Leoš, Libor, Lukas, Lubor, Jacob, Jakub, Josef, Jozef, Jirka, Jára, Pavel, Kamil, Karel, Boris, Jan, Tom, Ing, Ivo, Ota, Adam, Kaja, Kuba, Petr, Pepi, Honza, Pepa, Vít, Ivan, Marek, Matty, Milan, Mirek, Mirko, Míra, Míla, Aleš, Dave, and Vojta