This riddle doesn't have one universally agreed-upon "official" answer — it's a folk riddle that circulates with several different accepted solutions depending on the version you encounter. The most common answers given are:
- Your eyes — because the very first thing a newborn (or anyone waking up) does is open their eyes, making it the first thing "opened" in life or each day.
- A book — in versions framed around reading or learning, opening a book is treated as the "first" meaningful opening.
- Your mouth — since crying or making sound at birth involves opening the mouth before almost anything else happens.
Because riddles like this are passed around informally (in riddle books, chain emails, trivia apps, and social media), the wording and intended answer can vary by source. If you're trying to solve a specific version — for example, one that's part of a puzzle game, birthday trivia, or a chain of related riddles — the surrounding context or other clues in that set usually point to which answer is "correct" for that particular puzzle.
If your version pairs "first thing you open" with other riddles about the body or about a day's routine (like "what closes at night" or "what do you use to see"), it's almost certainly looking for eyes. If it's part of a set about objects or actions (like reading, gifts, or doors), a book or a door might be the intended fit.
Since there's no single official source for this riddle, treat it as one with multiple valid interpretations rather than one fixed correct answer.