Medium
Puzzles & Logic
Reasoning & Riddles
Classic puzzles and the logic that makes them work.
Sample question
Start quiz
A standard sudoku grid is what size?
Puzzles & Logic
Games of reasoning and the thinking behind them.
Puzzles are reasoning with the stakes removed, which is why they survive in every culture that has had spare time. This category covers the classic games and their structures, chess, sudoku, crosswords, tangrams, along with the vocabulary of formal reasoning that sits underneath them. It is less about being quick than about recognising the shape of a problem, which is a skill that transfers well beyond puzzles. The explanations describe why a rule or a method works rather than simply stating it, and none of the questions depend on solving anything against a clock.
Difficulty mix
New to Puzzles & Logic? Start here
Reasoning & Riddles
Classic puzzles and the logic that makes them work.
2 medium
1 hard
7–8 min each
3 quizzes in Puzzles & Logic
Hard
Puzzles & Logic
Chance, Odds and Bad Intuition
Coincidences, false positives and the places where reasoning about probability reliably fails.
Sample question
Start quiz
The gambler's fallacy is the belief that what?
Medium
Puzzles & Logic
Classic Puzzles and How They Work
Hanoi, Konigsberg, magic squares and the structures hiding underneath famous puzzles.
Sample question
Start quiz
In the Tower of Hanoi, which rule must never be broken?
Questions
About Puzzles & Logic quizzes
How many Puzzles & Logic quizzes are there?
3 published quizzes in this subject, 30 questions in total. Every one is researched, written and checked by hand.
How hard are they?
The mix here is 2 medium and 1 hard. Difficulty is about how obscure the answers are, not how fast you have to be — there is no timer on any quiz.
How long does one take?
About 7 minutes on average, ranging from 7 to 8. Playing every puzzles & logic quiz would take roughly 22 minutes.
Which one should I start with?
"Reasoning & Riddles" is the gentlest way in — 10 questions, about 7 minutes, rated medium.
Do I need an account?
No. Every quiz is free and playable straight away. An optional free account only saves your scores across devices.
Do you explain the answers?
Yes — every question has a short explanation of why the right answer is right, shown the moment you answer, whether you got it or not.