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Brain Teasers
25 linksRiddles, logic puzzles, lateral thinking and mind-stretchers — all in one place.
Daily & Weekly Challenges
- Braingle Daily Teaser
Fresh riddle daily.
- NPR Sunday Puzzle
Weekly on-air challenge.
- Car Talk Puzzler
Automotive brain-twisters.
Riddles & Logic Sites
- Riddles.com
10k+ graded riddles.
- Brainzilla
Logic grids & lateral puzzles.
- Logic-Puzzles.org
Interactive grids.
- BrainDen
Paradoxes, illusions, riddles.
Pencil Puzzles
- Simon Tatham's Puzzles
40 free logic puzzles, every platform.
- GMPuzzles
Championship quality by top constructors.
- Nikoli
The Japanese originators of Sudoku.
Puzzle Hunts
- MIT Mystery Hunt
The legendary annual hunt.
- Puzzled Pint
Casual monthly pub puzzles.
- Puzzle Hunt Calendar
Every upcoming hunt.
Math Challenges
- Project Euler
Math/programming problem series.
- Cut-the-Knot
Interactive math miscellany.
Brain-Training Apps
- Lumosity
Daily brain workouts.
- Elevate
Personalized brain games.
- Brilliant.org
Interactive STEM puzzles.
Communities
- r/riddles
Share & solve riddles.
- r/puzzles
1M+ enthusiasts.
- Puzzling StackExchange
Ask, solve, discuss.
Tutorials & Learning
- ThinkFun Classroom
Educator guides.
- Mensa for Kids Logic Lessons
Printable plans.
- How to Solve It (Polya, free PDF)
Problem-solving classic.