50 free Color trivia questions with answers. Color sits at the crossroads of physics, chemistry, biology and culture, which makes it unusually good trivia territory. This quiz covers the science (why the sky is blue, what the K in CMYK stands for, how many cone types you have and how many a mantis shrimp has), the history of pigments and dyes (Tyrian purple, mauveine, ultramarine, Indian yellow, cochineal, mummy brown), colors in art and branding (Yves Klein, Vantablack, Tiffany Blue, Pantone), flags, animals, and the strange history of color words in language, from Homer's wine-dark sea to Japanese blue traffic lights. Roughly a third of the questions are easy enough for a family round; the rest climb steadily to a handful of expert-level chemistry and history questions that will separate the pub-quiz regulars from everyone else. Every answer was checked against a primary source, mostly Wikipedia's science, art and history articles, and each question shows its citation, so you can settle any argument at the table.
30 of 50 questions with answers and explanations. Play the quiz
Q 01In the mnemonic ROYGBIV for the colours of the rainbow, what does the I stand for?
Indigo
British schoolchildren learn the same order as 'Richard Of York Gave Battle In Vain', a nod to the Duke of York's death at the Battle of Wakefield in 1460.
Q 02Newton first split the spectrum into five colours. Why did he later add two more to make seven?
To match the number of musical notes in a major scale
Newton was also the first person to use the word 'spectrum' in print for the band of colours, in 1671.
Q 03Which colour of visible light has the longest wavelength?
Red
The human eye responds to wavelengths from roughly 380 to 750 nanometres, and this colour sits at the top of that range.
Q 04The daytime sky is blue because of what physical effect, named after a British physicist?
Rayleigh scattering
Lord Rayleigh's 1871 explanation is a textbook example of solving a physics problem by dimensional analysis alone.
Q 05In the CMYK printing model, what does the K stand for?
Key
The black plate was the 'key' plate that the other three colour plates were aligned to.
Q 06How many types of colour-sensing cone cell does a typical human retina have?
Three
You have only about six or seven million cones, versus roughly 92 million rods that see in low light but not in colour.
Q 07Which animal's eyes contain 12 to 16 types of photoreceptor cell and can detect circularly polarised light?
Mantis shrimp
Despite all that hardware, tests suggest they are surprisingly poor at telling similar hues apart; their eyes seem built for speed, not subtlety.
Q 08Which is the most common form of colour blindness in humans?
Red–green
The genes involved sit on the X chromosome, so it shows up in around 1 in 12 men but only about 1 in 200 women.
Q 09Colour blindness is sometimes called 'daltonism' after which English chemist?
John Dalton
DNA analysis of his preserved eye tissue in 1995 confirmed he was a deuteranope, lacking working green-sensitive cones.
Q 10Blue eyes contain no blue pigment. Their colour comes from the same effect that makes what else blue?
The sky
Roughly 79% of the world's population has brown eyes, and every blue-eyed person is thought to descend from a single ancestral mutation.
Q 11Which pigment, with brown-black and red-yellow forms, is the primary determinant of human skin colour?
Melanin
Ginger hair is a small amount of the dark form mixed with plenty of the red-yellow form, pheomelanin.
Q 12Chlorophyll makes leaves green by absorbing light most strongly in which two colours?
Blue and red
The molecule holds a magnesium atom at its centre, where the structurally similar haem in your blood holds iron.
Q 13Magenta is described as an 'extra-spectral' colour. What does that mean?
No single wavelength of light produces it
Q 21Scheele's green, a popular Victorian pigment, was dangerous because it contained which element?
Arsenic
Napoleon's rooms on St Helena were painted in his favourite green, which fuelled a long-running poisoning theory that later research rejected in favour of stomach cancer.
Q 22The word for the dye that colours blue jeans comes from a Greek word meaning what?
Indian
The plant-based dye was largely replaced after BASF industrialised a synthetic version in 1897, building on Adolf von Baeyer's chemistry.
Q 23Which French artist registered his signature ultramarine paint, known as IKB, in 1960?
Yves Klein
The trick was not the pigment but the binder, a synthetic resin that let the ultramarine keep its raw powdery intensity once dry.
Your brain invents it when red-sensitive and blue-sensitive cones fire together with the green ones quiet, closing the colour wheel into a loop.
Q 14Tyrian purple, the dye reserved for Roman emperors, was extracted from what?
Sea snails
Twelve thousand Murex brandaris snails yielded about 1.4 grams of dye, enough to colour just the trim of one garment.
Q 15In 1856, William Henry Perkin discovered the dye mauveine while trying to make what?
Quinine
The failed malaria-drug experiment left a purple residue in his flask, and the colour was so popular from 1859 to 1861 that the era is nicknamed the 'mauve decade'.
Q 16Renaissance ultramarine was ground from lapis lazuli mined mainly in which modern country?
Afghanistan
Its name means 'beyond the sea', and it was so precious that artists saved it almost exclusively for the robes of the Virgin Mary.
Q 17A Bihar-made painters' pigment named for its country of origin reportedly came from the urine of cows fed on what?
Mango leaves
The cattle were reportedly kept malnourished on the diet, and the process was allegedly outlawed as inhumane in 1908, though no record of that law has ever been found.
Q 18The red dye carmine, still used in food and cosmetics, is made from which creature?
A cactus-dwelling scale insect
It takes about 70,000 cochineal insects to make a single pound of dye, and in colonial Latin America it was the second most valuable export after silver.
Q 19'Mummy brown', a pigment sold to artists into the 20th century, was made from what?
Ground-up Egyptian mummies
When Edward Burne-Jones learned in 1881 what was in his tube, he insisted on giving it a decent burial in his garden.
Q 20Prussian blue, the first modern synthetic pigment, was made by accident around 1706 in which city?
Berlin
Taken orally, the same compound is a WHO essential medicine, used as an antidote to thallium and radioactive caesium poisoning.
Q 24Vantablack, one of the darkest substances ever made, absorbs up to 99.965% of visible light using what?
Vertically aligned carbon nanotubes
Surrey NanoSystems handed the artist Anish Kapoor exclusive rights to use it in art, which triggered a memorable feud with the rest of the art world.
Q 25YInMn Blue, found by accident at Oregon State in 2009, is named for yttrium, indium and which third element?
Manganese
Crayola's 2017 crayon 'Bluetiful' was inspired by it, though the actual crayon contains none of the pigment.
Q 26Picasso's Blue Period, from 1901 to 1904, was directly followed by which of his periods?
Rose
Picasso said he started painting in blue after learning of his friend Carlos Casagemas's suicide, though he was not in Paris when it happened.
Q 27The name Crayola was coined by Alice Binney from 'ola', for oily, and 'craie', the French word for what?
Chalk
The company sold crayons as Binney & Smith for over a century before renaming itself Crayola LLC in 2007.
Q 28Crayola's 'Peach' crayon carried what name for most of the years between 1903 and 1962?
Flesh
The same crayon was briefly called Pink Beige in the late 1950s before the company settled on the fruit.
Q 29Which sky-blue shade was Pantone's very first Color of the Year, for 2000?
Cerulean
The company hyped it as the 'colour of the millennium'; the only year with two winners was 2016, when Rose Quartz shared the title with Serenity.
Q 30Which warm brown shade did Pantone name its Color of the Year for 2025?
Mocha Mousse
It followed the soft orange Peach Fuzz of 2024, and was in turn succeeded by the near-white Cloud Dancer for 2026.