How to use it
Type the word with ? for each hidden letter, for example ?A??A?, and list the letters you have already guessed wrongly. The solver shows every word that fits and ranks the letters you have not tried.
Why the percentages matter
A letter that appears in 90% of the remaining words is an almost safe guess. A letter near 50% splits the list in half, which is the fastest way to narrow things down when you have guesses to spare.
In hangman, a correct letter is revealed everywhere it appears, so the solver rules out words where a revealed letter would sit in a hidden square.