Looking for brain teasers for adults? Below are 12 original puzzles, written for this page, covering logic, numbers, patterns, words and spatial thinking. The answers are in a separate section so you can try first. You will also find the main types of brain teasers and simple ways to get better at solving them.
Logic puzzles: a few clues, one answer. You rule things out until only one option fits.
Number puzzles: short word problems you can solve with simple arithmetic or a little algebra.
Pattern puzzles: find the rule behind a sequence and predict what comes next.
Word puzzles: anagrams, missing words and odd-one-out lists.
Spatial puzzles: picture shapes, directions or angles in your head.
Trick questions: puzzles built so your first instinct is wrong. Slowing down is the whole skill.
Grab a pen. Some of these are easier with a quick sketch.
Movie seats (logic). Ana, Ben, Cal and Dee sit in a row of four seats, numbered 1 to 4 from left to right. Cal is in seat 1. Ben is not in an end seat. Ana sits in the seat directly to the right of Dee. Who sits where?
The last donut (logic). Someone in the office ate the last donut. Pat says, "Sam ate it." Sam says, "I didn't eat it." Lee says, "I didn't eat it." Exactly one of them is telling the truth. Who ate the donut?
Day check (trick question). If the day after tomorrow is Saturday, what day was the day before yesterday?
Swap the digits (numbers). I am a two-digit number. My digits add up to 11. If you swap my digits, you get a number that is 27 bigger than me. What number am I?
Birthday math (numbers). A mother is 30 years older than her son. In 5 years, she will be exactly three times his age. How old is the son now?
The stairs (trick question). Walking at a steady pace, you climb from the 1st floor to the 3rd floor in 30 seconds. Every floor has the same number of steps. How long will it take to climb from the 1st floor to the 6th floor?
Doubling pattern (patterns). What comes next: 2, 3, 5, 9, 17, ?
Growing gaps (patterns). What comes next: 3, 6, 11, 18, 27, ?
Missing word (words). What one word can follow KEY, CUP and DASH to make three new words?
Same letters (words). Three six-letter words use exactly the same letters. One means very quiet, one means to pay attention with your ears, and one means to sign up for the army. What are they?
Odd one out (words). Violin, cello, flute, harp, guitar. Which one does not belong, and why?
Clock angle (spatial). What is the smaller angle between the hour hand and the minute hand of a clock at 9:20?
Cal, Ben, Dee, Ana. Ben must be in seat 2 or 3. If Ben were in seat 3, Dee and Ana would be split between seats 2 and 4 and could not sit side by side. So Ben is in seat 2, Dee in seat 3 and Ana in seat 4.
Lee. Test each person. If Pat ate it, Sam and Lee are both telling the truth. If Sam ate it, Pat and Lee are both telling the truth. Only if Lee ate it is exactly one statement true (Sam's).
Tuesday. If Saturday is the day after tomorrow, today is Thursday, and two days before Thursday is Tuesday.
47. Swapping gives 74, and 74 minus 47 is 27. The digits 4 and 7 add up to 11.
10. The son is 10 and the mother is 40. In 5 years they will be 15 and 45, and 45 is three times 15.
75 seconds. Going from floor 1 to floor 3 is only two flights, so each flight takes 15 seconds. Floor 1 to floor 6 is five flights, and 5 times 15 is 75. The tempting quick answer is 90.
33. Each number is double the one before, minus 1. Double 17 is 34, minus 1 is 33.
38. The gaps grow by 2 each time: 3, 5, 7, 9, then 11. So 27 plus 11 is 38.
BOARD. Keyboard, cupboard and dashboard.
SILENT, LISTEN and ENLIST. All three use the letters E, I, L, N, S and T.
Flute. It is a wind instrument. The other four have strings.
160 degrees. The minute hand points at the 4, which is 120 degrees from 12. The hour hand has moved a third of the way from 9 to 10, so it sits at 280 degrees. 280 minus 120 is 160.
Read the question twice. Words like "exactly," "only" and "not" carry the puzzle.
Get it on paper. Draw the seats, list the days or write the equation. Paper holds the details so your head can do the thinking.
Test each case. When there are only a few options, like three suspects, try each one and see which fits every clue.
Check your answer against every clue. A guess that fits two clues out of three is still wrong.
Distrust your first instinct on trick questions. The stairs puzzle catches people because the quick answer feels right.
Step away when stuck. A meta-analysis in Psychological Bulletin found a positive incubation effect, which means setting a problem aside for a while before trying again helped people solve it. Longer work on the problem before the break gave a bigger effect, and filling the break with a mentally demanding task gave a smaller one. So give it a real try first, then do something easy like the dishes or a short walk.
Mix the types. Rotate logic, number, word and spatial puzzles so you build a wider set of tricks. For more, see our sister site's guides to logic puzzles for adults and word games for adults.
Keep expectations honest. A review summarized by the Association for Psychological Science found that brain-training tasks seem to improve performance on the trained tasks themselves, with very little evidence that they improve everyday cognitive performance. In other words, puzzles make you better at puzzles. That is still a fine reason to do them, and Mayo Clinic lists puzzles alongside reading, games, music and new hobbies as ways to stay mentally active.
A mix works best: logic puzzles with a few clues, number puzzles, pattern sequences, word puzzles and spatial questions like clock angles. Start with puzzles you can solve in a few minutes, then move up.
They are a good way to stay mentally active, and Mayo Clinic lists puzzles among activities that engage your mind. Research suggests the skills mostly improve on the puzzles you practice, not across everyday life.
Read carefully, write things down, test each possible case and check your answer against every clue. Regular practice with a mix of types helps you spot common patterns.
Take a break after a solid attempt. A meta-analysis found that setting a problem aside before trying again helps, especially if the break is filled with something easy rather than another hard mental task.
If you want a fresh set every day, Cognilo: Brain Training Games serves five short puzzles in about six minutes, drawn from eight puzzle types across memory, logic, numbers, spatial reasoning, focus and language. You can play untimed, timed or unrated, and after each round it gives a strategy tip and replays any missed round with the correct answer. It is free with optional Pro purchases, and it has no account, no ads and no tracking.
Get Cognilo free on the App Store
Does incubation enhance problem solving? A meta-analytic review (Psychological Bulletin, via PubMed)
Do "Brain-Training" Programs Work? (Association for Psychological Science)