woman pondering with fingers pressed together just under chin
Sarah Biren
Sarah Biren
September 20, 2023 ·  3 min read

15 Brain Teasers That Will Awaken Your Inner Sherlock Holmes

Crime and mystery is an extremely popular genre — and for good reason! Aside from their fast pace and interesting characters, what people love most is trying to solve the puzzle. Take Sherlock Holmes stories, for instance. In every adaptation of the detective, the audience is trying to use the clues to guess the ending. And when they get it right, it’s beyond satisfying. It’s like we have an inner Sherlock Holmes who can determine answers from tiny details, and this spirit arises with brain teasers as well. The goal is the same: Can you guess the true answer?

Each of these puzzles is followed immediately by the answer, so don’t scroll until you are ready to check your guess. How many could you get right?

15 Brain Teasers For Your Inner Sherlock Holmes.

Riddle #1 A new one every month

No matter how little or how much you use me, you change me every month. What am I?

Answer: A calendar.

Riddle #2 Whole or nothing

On my side, I am everything. Cut me in half and I am nothing. What am I?

Answer: The number 8

Riddle #3 What time is it?

Of all the time-measuring mechanisms, the sundial has the fewest moving parts. Which one has the most?

Answer: An hourglass

Riddle #4 Eight equals four

How can 8 + 8 = 4?

Answer: In terms of time. 8 AM + 8 hours = 4 PM

Riddle #5 Red to black brain teasers

Take one out and scratch my head. I am now black but once was red. What am I?

Answer: A matchstick

Riddle #6 Guess the next letters

G T N T L… Guess the next three letters in the sequence.

Answer: I T S. The sequence is the first letter of every word in the previous sentence.

Riddle #7 Bird’s eye view

Brain teaser "which is the correct bird's eye view"
Photo Credits: Brightside

Answer: A

Riddle #8 The other side of the river

A man calls his dog from the other side of the river. The dog obediently crosses the river. The dog didn’t use a boat or a bridge but his fur remained dry. How is this possible?

Answer: The river was frozen.

Riddle #9 Nail in a tree brain teasers

Sam stuck a nail into a tree. A decade later, he went back to see the nail. If the tree grew 5 cm every year, how much higher is the nail?

Answer: It’s at the same spot. Trees grow from their tops, not their roots.

Riddle #10 Who’s in the photo?

A man examines a photograph of another person. He’s asked who’s in the photo. The man responds, “Brothers and sisters, I have not. But that man’s father is my father’s son.” Who is in the photo?

Answer: His son

Riddle #11 Fathers and sons

Two fathers and two sons went fishing and caught three fish. They went home and cooked their catch, which was enough to serve one fish per person. How is this possible?

Answer: There were three people to eat the three fish. There was the grandfather, the father, and the son/grandson.

Riddle #12 Balls and billiards brain teasers

Brain teaser with billiard balls
Photo Credits: Brightside

Choose three balls to total 30. 

Answer: Turn the 9 ball upside down to make it 6. Then add 11 + 13 to make 27. Then add 6 to make a total of 30.

Riddle #13 Walking in the rain

A man walks in the rain in the middle of nowhere with no umbrella or shelter around. When he returned home, not a single hair on his was wet. How is this possible?

Answer: The man was bald.

Riddle #14 In and out

You throw me out when you use me. You take me in when you don’t use me. What am I? 

Answer: An anchor

Riddle #15 Not twins

A woman had two sons born within the same hour, day, and year. But they were not twins. How is this possible?

Answer: They were two sons in a set of triplets.

How many brain teasers did you get right? Which ones did you get wrong? Pass these on to a friend to see how many correct answers they get!

If you’re looking to have some more brain teaser and puzzle fun, check these out!