Claim the greens
Every exact-position match is marked first and removes one copy of that letter from the answer's remaining supply.
Repeated-letter scoring
Why did that letter turn gray?
Gray usually means “not in the word.” With repeated letters it can mean something more precise: there is no extra copy left. Wordle gives out greens first, then yellows, and never awards more colored tiles for a letter than the answer actually contains.
Try it yourself
Put two words on the table
The words do not have to be accepted guesses; this demo is only about the coloring rule.
How the scoring works
Score greens first, then yellows
Hand out yellows
For each unmatched guess tile, Wordle checks whether an unused copy of that letter remains elsewhere.
Leave the extras gray
Once all copies in the answer have been claimed, additional copies in the guess stay gray—even if the letter appears elsewhere.
Two examples