★7% of American adults believe that chocolate milk comes from brown cows.★The Dutch were once the tallest people in the world.★Pineapples take about two years to grow.★A blue whale's tongue can weigh as much as an elephant.★There are more than 1,000 chemicals in a cup of coffee.★The longest hiccuping spree lasted 68 years.★A group of owls is called a parliament.★There are only two countries in the world whose names start with 'The': The Gambia and The Bahamas.★Your nose can remember 50,000 different scents.★A group of crows mobbing a predator is literally called a 'murder patrol'.★A group of ferrets is called a business.★A 'moment' was medieval unit of time equal to 90 seconds.★A rhinoceros' horn is made of keratin, the same stuff as hair.★Koalas have fingerprints nearly identical to humans.★Pteronophobia is the fear of being tickled by feathers.★A snail can have up to 25,000 teeth on its tongue.★The 'new car smell' is made of dozens of chemicals off-gassing from the interior.★Cows have best friends and get stressed when separated.★A 'jiffy' is one trillionth of a second in physics.★Wombat poop is cube-shaped.★Pigs can't look up at the sky without rolling over.★The dot over the letter 'i' is called a tittle.★Tigers have striped skin, not just striped fur.★Bees can recognize individual human faces.★The shortest commercial flight in the world lasts just 57 seconds.★A group of flamingos is called a 'flamboyance'.★The smell of rain has a name: petrichor.★Scotland's national animal is the unicorn.★A flock of crows is known as a murder.★More than half of all people alive today have never made a phone call.★The microwave oven was invented by accident when a researcher noticed a chocolate bar melted in his pocket.★Banging your head against a wall for one hour burns 150 calories.★Humans share 60% of their DNA with bananas.★Sea otters hold hands while sleeping so they don't drift apart.★Hippos can't actually swim, they walk along the riverbed.★Avocados are toxic to most animals except humans.★Butterflies taste with their feet.★Google processes more than 8.5 billion searches every single day.★The French language has 13 different words for 'kiss'.★Bananas are curved because they grow towards the sun.★A hummingbird's heart can beat up to 1,260 times per minute.★Octopuses have three hearts and blue blood.★Chewing gum while you chop onions helps keep you from crying.★Humans are the only animals that blush.★It is physically impossible to hum while holding your nose.★A lion's roar can be heard from up to 5 miles away.★Sloths can hold their breath longer than dolphins can.★A newborn kangaroo is about the size of a jellybean.★The Great Wall of China is not visible from space with the naked eye.★A blue whale's heart is roughly the size of a small car.★Horses physically cannot vomit.★There is a village in Norway called 'Hell' that freezes over every winter.★Sharks existed on Earth before trees did.★If you lift a kangaroo's tail off the ground it can't hop.★A day on Jupiter lasts only about 10 hours.★The inventor of the Pringles can is buried in one.★Goldfish can recognize human faces.★The first item ever sold on eBay was a broken laser pointer.★A day on Venus is longer than a year on Venus.★Hot water freezes faster than cold water. This is called the Mpemba effect.★A group of pandas is called an embarrassment.★The Hawaiian alphabet has only 13 letters.★A crocodile can't stick its tongue out.★Cashews grow on the outside of a fruit, not inside a shell.★We have mapped more of Mars than of our own ocean floor.★Elephants are the only mammals that can't jump.★Pigeons can recognize themselves in a mirror.★The first oranges weren't orange, they were green.★A group of jellyfish is called a smack.★The first computer mouse was made of wood.★The smell of freshly cut grass is actually a plant distress signal.★Most 'silver' spoons are actually made of stainless steel.★Peanuts aren't nuts, they are legumes.★The shortest war in history lasted 38 to 45 minutes between Britain and Zanzibar.★A cloud can weigh more than a million pounds.★Sloths only poop about once a week.★An octopus has nine brains.★Cleopatra lived closer in time to the Moon landing than to the building of the Great Pyramid.★Dolphins sleep with one eye open.★Voice actors for Mickey and Minnie Mouse got married in real life.★Barbie's full name is Barbara Millicent Roberts.★A day on Mercury lasts 59 Earth days.★A snail can sleep for three years straight.★Antarctica is the only continent without native reptiles or snakes.★Cats can't taste sweetness.★Sea cucumbers breathe through their butts.★So far, two diseases have successfully been eradicated: smallpox and rinderpest.★The average person spends six months of their life waiting for red lights to turn green.★Ancient Egyptians slept on stone pillows.★You can hear a blue whale's heartbeat from more than two miles away.★The oldest 'your mom' joke was discovered on a 3,500 year old Babylonian tablet.★The human brain uses about 20% of the body's total energy.★The Mona Lisa has no eyebrows or eyelashes.★The average person walks the equivalent of three times around the world in a lifetime.★It takes about eight minutes for sunlight to reach Earth.★Polar bears have black skin under their white fur.★There's a species of jellyfish that is immortal.★There are more stars in the universe than grains of sand on every beach on Earth.★Dolphins have names for each other.★Snakes can help predict earthquakes.★A group of frogs is called an army.★Cherophobia is an irrational fear of fun or happiness.★The moon has moonquakes.★A group of porcupines is called a prickle.★Dragonflies have been around for about 300 million years.★Crows can recognize human faces and hold grudges for years.★Saturn would float if you could find an ocean big enough.★Bubble wrap was originally invented as wallpaper.★Vincent van Gogh only sold one painting during his lifetime.★The Eiffel Tower can grow up to 6 inches taller during summer.★A jiffy is an actual unit of time: 1/100th of a second.★There are more possible iterations of a game of chess than atoms in the observable universe.★Ketchup was once sold as medicine in the 1830s.★A newborn panda is smaller than a mouse.★The world's oldest known recipe is for beer.★A shrimp's heart is located in its head.★A mosquito has 47 teeth.★Octopuses can taste with their arms.★Your stomach gets a new lining every 3 to 4 days, otherwise it would digest itself.★Ostriches can run faster than horses.★A bolt of lightning is five times hotter than the surface of the sun.★Humans blink about 15 to 20 times per minute.★Cotton candy was co-invented by a dentist.★29th May is officially Put a Pillow on Your Fridge Day.★In Switzerland it is illegal to own just one guinea pig.★Bananas are berries, but strawberries are not.★Cows have regional accents, they moo differently in different areas.★The Statue of Liberty was originally intended to be a lighthouse.★Honey never spoils. Archaeologists found 3000-year-old honey in Egyptian tombs that was still edible.★The longest recorded flight of a chicken lasted 13 seconds.★Rats laugh when tickled.★Your tongue print is as unique as your fingerprint.★Nintendo was founded in 1889 as a playing card company.★The fear of long words is ironically called hippopotomonstrosesquippedaliophobia.★Starfish can regenerate their lost limbs.★A hippo's sweat is pink.

★7% of American adults believe that chocolate milk comes from brown cows.★The Dutch were once the tallest people in the world.★Pineapples take about two years to grow.★A blue whale's tongue can weigh as much as an elephant.★There are more than 1,000 chemicals in a cup of coffee.★The longest hiccuping spree lasted 68 years.★A group of owls is called a parliament.★There are only two countries in the world whose names start with 'The': The Gambia and The Bahamas.★Your nose can remember 50,000 different scents.★A group of crows mobbing a predator is literally called a 'murder patrol'.★A group of ferrets is called a business.★A 'moment' was medieval unit of time equal to 90 seconds.★A rhinoceros' horn is made of keratin, the same stuff as hair.★Koalas have fingerprints nearly identical to humans.★Pteronophobia is the fear of being tickled by feathers.★A snail can have up to 25,000 teeth on its tongue.★The 'new car smell' is made of dozens of chemicals off-gassing from the interior.★Cows have best friends and get stressed when separated.★A 'jiffy' is one trillionth of a second in physics.★Wombat poop is cube-shaped.★Pigs can't look up at the sky without rolling over.★The dot over the letter 'i' is called a tittle.★Tigers have striped skin, not just striped fur.★Bees can recognize individual human faces.★The shortest commercial flight in the world lasts just 57 seconds.★A group of flamingos is called a 'flamboyance'.★The smell of rain has a name: petrichor.★Scotland's national animal is the unicorn.★A flock of crows is known as a murder.★More than half of all people alive today have never made a phone call.★The microwave oven was invented by accident when a researcher noticed a chocolate bar melted in his pocket.★Banging your head against a wall for one hour burns 150 calories.★Humans share 60% of their DNA with bananas.★Sea otters hold hands while sleeping so they don't drift apart.★Hippos can't actually swim, they walk along the riverbed.★Avocados are toxic to most animals except humans.★Butterflies taste with their feet.★Google processes more than 8.5 billion searches every single day.★The French language has 13 different words for 'kiss'.★Bananas are curved because they grow towards the sun.★A hummingbird's heart can beat up to 1,260 times per minute.★Octopuses have three hearts and blue blood.★Chewing gum while you chop onions helps keep you from crying.★Humans are the only animals that blush.★It is physically impossible to hum while holding your nose.★A lion's roar can be heard from up to 5 miles away.★Sloths can hold their breath longer than dolphins can.★A newborn kangaroo is about the size of a jellybean.★The Great Wall of China is not visible from space with the naked eye.★A blue whale's heart is roughly the size of a small car.★Horses physically cannot vomit.★There is a village in Norway called 'Hell' that freezes over every winter.★Sharks existed on Earth before trees did.★If you lift a kangaroo's tail off the ground it can't hop.★A day on Jupiter lasts only about 10 hours.★The inventor of the Pringles can is buried in one.★Goldfish can recognize human faces.★The first item ever sold on eBay was a broken laser pointer.★A day on Venus is longer than a year on Venus.★Hot water freezes faster than cold water. This is called the Mpemba effect.★A group of pandas is called an embarrassment.★The Hawaiian alphabet has only 13 letters.★A crocodile can't stick its tongue out.★Cashews grow on the outside of a fruit, not inside a shell.★We have mapped more of Mars than of our own ocean floor.★Elephants are the only mammals that can't jump.★Pigeons can recognize themselves in a mirror.★The first oranges weren't orange, they were green.★A group of jellyfish is called a smack.★The first computer mouse was made of wood.★The smell of freshly cut grass is actually a plant distress signal.★Most 'silver' spoons are actually made of stainless steel.★Peanuts aren't nuts, they are legumes.★The shortest war in history lasted 38 to 45 minutes between Britain and Zanzibar.★A cloud can weigh more than a million pounds.★Sloths only poop about once a week.★An octopus has nine brains.★Cleopatra lived closer in time to the Moon landing than to the building of the Great Pyramid.★Dolphins sleep with one eye open.★Voice actors for Mickey and Minnie Mouse got married in real life.★Barbie's full name is Barbara Millicent Roberts.★A day on Mercury lasts 59 Earth days.★A snail can sleep for three years straight.★Antarctica is the only continent without native reptiles or snakes.★Cats can't taste sweetness.★Sea cucumbers breathe through their butts.★So far, two diseases have successfully been eradicated: smallpox and rinderpest.★The average person spends six months of their life waiting for red lights to turn green.★Ancient Egyptians slept on stone pillows.★You can hear a blue whale's heartbeat from more than two miles away.★The oldest 'your mom' joke was discovered on a 3,500 year old Babylonian tablet.★The human brain uses about 20% of the body's total energy.★The Mona Lisa has no eyebrows or eyelashes.★The average person walks the equivalent of three times around the world in a lifetime.★It takes about eight minutes for sunlight to reach Earth.★Polar bears have black skin under their white fur.★There's a species of jellyfish that is immortal.★There are more stars in the universe than grains of sand on every beach on Earth.★Dolphins have names for each other.★Snakes can help predict earthquakes.★A group of frogs is called an army.★Cherophobia is an irrational fear of fun or happiness.★The moon has moonquakes.★A group of porcupines is called a prickle.★Dragonflies have been around for about 300 million years.★Crows can recognize human faces and hold grudges for years.★Saturn would float if you could find an ocean big enough.★Bubble wrap was originally invented as wallpaper.★Vincent van Gogh only sold one painting during his lifetime.★The Eiffel Tower can grow up to 6 inches taller during summer.★A jiffy is an actual unit of time: 1/100th of a second.★There are more possible iterations of a game of chess than atoms in the observable universe.★Ketchup was once sold as medicine in the 1830s.★A newborn panda is smaller than a mouse.★The world's oldest known recipe is for beer.★A shrimp's heart is located in its head.★A mosquito has 47 teeth.★Octopuses can taste with their arms.★Your stomach gets a new lining every 3 to 4 days, otherwise it would digest itself.★Ostriches can run faster than horses.★A bolt of lightning is five times hotter than the surface of the sun.★Humans blink about 15 to 20 times per minute.★Cotton candy was co-invented by a dentist.★29th May is officially Put a Pillow on Your Fridge Day.★In Switzerland it is illegal to own just one guinea pig.★Bananas are berries, but strawberries are not.★Cows have regional accents, they moo differently in different areas.★The Statue of Liberty was originally intended to be a lighthouse.★Honey never spoils. Archaeologists found 3000-year-old honey in Egyptian tombs that was still edible.★The longest recorded flight of a chicken lasted 13 seconds.★Rats laugh when tickled.★Your tongue print is as unique as your fingerprint.★Nintendo was founded in 1889 as a playing card company.★The fear of long words is ironically called hippopotomonstrosesquippedaliophobia.★Starfish can regenerate their lost limbs.★A hippo's sweat is pink.

Stroop test

Time

30

Score

0

Best

0

Stroop test

Tap the color the word is painted in. The word itself is a trick.

REDtap blue

Press space to start.

How to play Stroop test

A word for a colour appears on screen, painted in a different colour. Your job is to tap the colour the word is painted in, not the word itself. So if the word RED is shown in blue ink, you tap blue. The faster you tap right, the more points. Wrong taps lose points. The clock runs for thirty seconds.

Tips

Look at the colour first, read the word second
Lower your reading reflex, focus on the ink
If your brain freezes, blink and try the next one
Practice once a day, the conflict gets easier with reps

About Stroop test

John Ridley Stroop published the experiment in 1935 in his PhD thesis. Reading is so automatic in adult brains that the word fights with the colour, slowing your reaction time. The Stroop effect is still used in psychology and neurology today, including in tests for ADHD and dementia. The mini version we run here is not a clinical tool, just a quick brain twister that shows you how fast your reading kicks in even when you do not want it to.

More reflex games

Math sprint: Solve as many math sums as you can in 60 seconds.
Snake: A modern take on the classic. Don't bite your tail.
Aim trainer: Click as many targets as you can in 30 seconds.
Reaction time: How fast can you click when the screen turns green?
Whack a mole: Bonk the moles before they pop back into their holes.
Color match: Tap when the two colours line up. Sounds simple, gets fast.

Browse the full arcade →

00:00Warming up

0Pixels scrolled

0.0cmMouse odyssey

0Clicks made

0.00Calories burned

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