Seven Mind Blowing Brain Teasers

We’ve collected some of the hardest brain teasers online to get your mind working out. These puzzles will train your brain, improve your cognition and when you solve them, even give you a Dopamine release that will improve your wellbeing and mental health. If you want to rack your brain, you’re in the right place. Click the triangle next to the question to reveal the answer. Let’s get started…

Ten Brain Teaser


Taking one from eleven makes it ten and taking one from nine also makes it ten. How? (Click the triangle for the answer).

Answer: Roman numerals. 11 = XI, 10 = X, 9 = IX

Knock Knock Brain Teaser


A man was sound asleep in a hotel when he was woken by a knock on his door. Bleary-eyed, he stumbled to the door and when he opened it, there was a stranger outside. The stranger said “Oh sorry, I thought this was my room” and promptly walked away and headed round the corner of the corridor. Immediately, the sleepy man called hotel security to advise them to call the police and arrest the stranger. Why? (Click the triangle for the answer).

Answer: If it was his room, the stranger would have had a key, so had no need to knock.

Brave Grandpa Brain Teaser


John and Steve, two friends, were discussing their grandparents. John shared some amazing stories about his brave Grandpa who fought in World War I. He said he was so brave he was given a medal engraved with “For the brave men who fought in World War I”. Steve instantly knew he was lying. How? (Click the triangle for the answer).

Answer: World War 1 wasn’t called World War I until after World War II.

Buried In Jersey Brain Teaser


Why is against the law for a man living in Manhatten to be buried in Jersey? (Click the triangle for the answer).

Answer: Because he’s not dead yet!

Car Crash Brain Teaser


A man and his son were involved in a car accident. Sadly, the man died on the journey to the hospital. The son was rushed into hospital. The ER surgeon said “I cannot operate on this boy, he’s my son!”. How is this possible? (Click the triangle for the answer).

Answer: The surgeon was his mother.

Airplane Brain Teaser


There was an horrific plane crash, killing every single person onboard. Two people survived. How? (Click the triangle for the answer).

Answer: They were married.

Pills Brain Teaser


Your doctor gives you three pills and informs you that you must take one every 30 minutes. How long would it take you to take all three pills? (Click the triangle for the answer).

Answer: One hour. You take one, wait 30 minutes, take the next, wait 30 minutes and take the final pill.

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