Odd One Out: General Knowledge — Rules & What Counts
Four options, one impostor — but here the categories roam everywhere: planets, chemical elements, string instruments, German car brands, Olympic sports, Shakespeare plays, mammals, bones. Each question names the category; you tap the one option that doesn't belong, and keep going until three misses have used up your lives.
It plays like the best pub-quiz moments: everyone "knows" Pluto, HTML and the penguin — right up until they have to commit. Every round closes with a one-line explanation (Pluto has been a dwarf planet since 2006; bronze is an alloy, not an element), so the quiz doubles as a rapid-fire fact refresher.
How to play
Read the question. Then tap the option that does not belong.
You get one pick for each round. There are no second guesses.
The quiz marks your answer immediately. It also gives one line that explains the answer.
You start with three lives. The hearts in the top bar show the lives that you have.
A correct answer gives one point. A wrong answer costs one life.
A round that costs a life gives no points. The quiz continues with the next round.
The run ends when you lose the third life. It also ends when you play all the rounds.
Select "Review rounds" on the result screen to see each round that you played.
What counts in this quiz
The quiz holds 100 categories — science, music, sport, literature, food and anatomy all rotate in. One run can use all of them.
Categories follow the standard definitions: the IAU's eight planets, the periodic table's elements, the Olympic programme as it stands.
Your score is the number of correct answers. The maximum score is 100 — every round in the quiz.
A wrong answer costs one life. You keep the points that you have.
The timer counts up from your first pick. It only separates equal scores on the leaderboard.
What's not included — and why
No opinion questions — every category has a factual, checkable membership (no "best" or "most famous").
No double-impostor rounds — exactly one of the four options is always out of place.
Good to know
When Pluto was reclassified in 2006, the demotion vote happened on the last day of an astronomy conference in Prague — most attendees had already flown home.
HTML is a markup language, not a programming language — it describes what a page is, not what it does, which is exactly why it's this quiz's favourite trap.
The platypus is such an odd mammal that when its skin first reached London in 1799, scientists inspected it for stitches, convinced it was a hoax.