  In this paper, we give a formal definition of the popular word-guessing game
Wordle. We show that, in general, determining if a given Wordle instance admits
a winning strategy is NP-complete. We also show that given a Wordle instance of
size $N$, a winning strategy that uses $g$ guesses in the worst case (if any)
can be found in time $N^{O(g)}$.
