Have you ever argued with someone over whether something is blue or green? That exact scenario led neuroscientist and programmer Patrick Mineault to create a viral online test that reveals how people perceive colors differently—and it’s sparked the curiosity of over 1.5 million users worldwide.
It All Started with a Blanket
The idea came to Mineault by chance during a casual argument with his wife. He insisted their blanket was “unambiguously green,” while she was convinced it was “unambiguously blue.” Rather than letting the debate end there, Mineault decided to turn the disagreement into a science experiment.
A Simple Game with Eye-Opening Results
He launched IsMy.Blue, a website where users are shown a series of color swatches and asked to classify each one as either blue or green. The colors get increasingly similar, testing the user’s ability to distinguish between the two tones. At the end of the game, the website compares your responses to others’—revealing whether you lean more toward “blue” or “green” than the average person.
For example, Mineault himself discovered that his blue-green boundary is 78% “more blue” than the average user’s.
More Than Just a Fun Game
The viral website, launched in August 2024, taps into a question that has fascinated philosophers and scientists for centuries: Do we all see the same colors?
“People’s perceptions are ineffable, and it is interesting to think that we have different views,” Mineault told The Guardian. This mirrors the fascination the world had with The Dress in 2015—a now-iconic photo that divided people over whether it was white and gold or black and blue.
While physiological factors like color blindness explain many differences in perception, cultural and linguistic influences may also play a role. For instance, ancient Greek lacked a word for “blue,” and in The Odyssey, Homer famously described the sea as “wine-dark.” Meanwhile, languages like Russian have multiple distinct words for different shades of blue.
Is the Test Scientifically Accurate?
Although the test is a fun tool for comparing color perception, Mineault is clear about its limitations. Device screens, lighting, and time of day can all affect how we see colors. To get the most accurate results, he recommends that people take the test under the same conditions—ideally on the same device, in the same lighting, and at the same time.
He’s now analyzing the data by country and may expand the experiment to other color combinations like yellow and green. While there are currently no plans to publish academic findings from the test, it’s already sparking global interest in how we each see the world.
Science Behind the Shades
Julie Harris, a professor of psychology at the University of St Andrews, notes that while vision scientists have long assumed that human visual perception is uniform, new evidence suggests that culture and environment may play a bigger role than once thought.