Choose two or three paints and set how much of each — the mixed color appears immediately — or paint them over each other on a palette and watch them blend. It is calculated the way real pigment absorbs light, not by averaging screen colors.
Paint mixing is subtractive: each pigment absorbs part of the light, so every color you add takes more light away and the mix gets darker and duller. That is why red, yellow and blue together make brown, not white.
Choose paints (up to 3) — a basic color or “Pick a color” for any shade
Real paint Calculated with the Kubelka–Munk model of how pigments absorb and scatter light
Screen average The RGB numbers simply averaged — why blue + yellow turns gray on a computer
Popular combinations
Paint on the brush
Paint a stripe of red, switch to yellow and cross it once. Where they overlap the paint is 1 part red to 1 part yellow — orange. Cross the same spot with yellow again and it becomes 2 yellow : 1 red, leaning toward yellow. The paint is opaque like acrylic, the brush always carries the color you picked, and hovering over the palette shows exactly which paints are mixed there.
Each square is a 1 : 1 mix. Tap a square to open it in the mixer.
🎨
—
Progress
0
Score
0
Streak
—
Accuracy
Why paint gets darker the more you mix
A paint looks colored because its pigment absorbs some wavelengths of light and reflects the rest. Ultramarine absorbs most of the red and yellow light that falls on it and sends back blue; a cadmium yellow absorbs the blue and violet and sends back the rest. Mix the two and each pigment keeps absorbing what it always absorbed, so only light that neither of them swallows can escape. That leftover band is green.
That is why mixing paint is called subtractive: every pigment you add can only take light away. Mixes therefore drift toward darker, less saturated colors, and three well-chosen primaries together leave almost nothing — a dark brown. The mixer on this page shows the effect directly: add a third paint to any pair and watch the result sink.
Painting colors over each other
The Paint & mix tab turns the calculator into a palette. Pick red, paint a stripe, then switch to yellow and cross it. Every pass of the brush adds one part of its paint to the spots it covers, so the crossing holds one part red and one part yellow and shows the same orange as the mixer. Cross it again with yellow and that spot now holds two parts yellow to one of red, a lighter, yellower orange. Hover over any spot to read its recipe, such as “Red 1 + Yellow 2”.
The paint is deliberately opaque, like acrylic or gouache, and the brush never picks up the color underneath. Real brushes do drag paint around, which is useful when painting but makes it hard to see what a mix produces; keeping each pass clean means the color you see always matches a simple ratio you can repeat with real paint.
The classroom primaries: red, yellow and blue
Most of us learned that red, yellow and blue are the primary colors and that orange, green and purple are the secondaries. The rule works well enough to teach color: red + yellow gives orange, yellow + blue gives green, red + blue gives purple. It is also why a basic school paint set contains exactly those three plus white and black — the first chart in the Mixing chart tab.
The weak spot is purple. A typical red pigment reflects very little blue, and a typical blue reflects very little red, so the light they share is thin and the purple comes out dark and muddy — exactly what the simulator shows. Painters who want a clean violet start from a magenta-leaning red or simply buy a violet tube, because no amount of mixing can put back light that the pigments have already absorbed.
The printing primaries: cyan, magenta and yellow
Look at the cartridges in an inkjet printer and you will not find red or blue. Printers use cyan, magenta and yellow, because each of them absorbs roughly one third of the spectrum and reflects the other two thirds. Any two of them overlap in exactly one third: cyan + yellow reflects green, magenta + yellow reflects red, cyan + magenta reflects blue. The result is a wider range of clean colors than red, yellow and blue can manage.
In theory all three together absorb everything and give black. Real inks are not perfect, and the mixer shows what actually happens: cyan + magenta + yellow comes out as a dark brown. That is why printers carry a fourth cartridge, black, labelled K — the CMYK you see in print settings. Black ink is also cheaper than spending three colored inks on every line of text.
White and black: tints, shades and tones
Adding white to a color makes a tint: red becomes pink, blue becomes sky blue, green becomes mint. Adding black makes a shade: red becomes burgundy, blue becomes navy, yellow becomes olive. Adding gray, or both white and black, makes a tone — a softer, quieter version of the color. Try the amount buttons in the mixer: two parts white to one part red gives a much lighter pink than one to one.
Black is powerful. It absorbs every wavelength, so a small amount changes a mix far more than the same amount of white. Painters usually add dark to light a little at a time, never the other way round, and many avoid black altogether for shadows because it deadens the color; mixing a complementary color, below, keeps the shadow alive.
Complementary colors cancel into brown and gray
Colors opposite each other on the color wheel — red and green, blue and orange, yellow and purple — absorb what the other reflects. Mixed in equal amounts they cancel toward a dark brown or gray, as red + green does in the mixer. Mixed in small amounts, a complement is the best way to calm a color down: a touch of green takes the shout out of a red without making it dirty the way black would.
This is also why mixing many colors together nearly always ends in the same muddy brown: with enough different pigments, every part of the spectrum is being absorbed by something.
Why a computer average gets paint wrong
A screen stores a color as three numbers for red, green and blue light. Averaging those numbers is what most apps do when they “blend” two colors, and for paint it gives the wrong answer: blue (30, 80, 180) and yellow (255, 213, 0) average to a dull gray-olive, not green. The two cards under the mixer show both results side by side.
This page instead uses the Kubelka–Munk model, a physical description of how layers of pigment absorb and scatter light, through the open-source spectral.js library. Each color is expanded into a reflectance curve across the visible spectrum, the absorption and scattering of the paints are combined in proportion to the amounts, and the result is turned back into a screen color. It is still a model: real tubes from different brands use different pigments, so treat the result as a reliable guide to direction rather than an exact match.
Getting the amounts right
Pigments differ in tinting strength — how strongly they color a mix. Most blues and blacks are strong and most yellows are weak, which is why one part blue to one part yellow already leans toward a deep green, and two parts yellow give a fresh yellow-green. The model on this page includes tinting strength, so the amount buttons behave the way paint does.
Start with the lighter color and add the darker one in small steps.
For pastels, start with white and add color, not the other way round.
To dull a color, reach for its complement before black.
Mix a little more than you need — matching a color a second time is hard.
Why do red, yellow and blue make brown instead of black?
In theory the three primaries absorb the whole spectrum between them. Real pigments are imperfect absorbers — each lets some light through in places it should block — and the leftovers are mostly in the red-orange range, so you see a dark brown. The same happens with cyan, magenta and yellow inks, which is why printers add black.
Is green a primary color or do you mix it?
It depends on whether you are mixing paint or light. With paint, green is a secondary: blue + yellow, or more brightly cyan + yellow. With light, green is one of the three primaries, and red + green light makes yellow. The light color mixing page shows the additive side.
How do I mix skin tones, peach or sky blue?
Most light colors are a hue plus plenty of white. Sky blue is blue with about the same amount of white; pink is red with white; peach is red and yellow with two parts white. Skin tones start from that peach and are adjusted with a touch of brown or a little blue to cool them. Try these in the mixer with the amount buttons.
Can I mix a color I picked myself?
Yes. Press “Pick a color”, choose from the gradient or type a HEX code such as #E67E22 or rgb(230,126,34), and add it as a paint. It joins the palette and can be mixed with any other paint, up to three at a time. The model treats it as a paint that looks like that color, so results for unusual colors are an approximation.
Why does my real paint look a little different?
Different brands use different pigments under the same color name, and some pigments are transparent while others are opaque. Paper, how wet the paint is and your screen's calibration all shift what you see. The simulator gets the direction of a mix right — which way it leans and whether it goes dark or dull — but a specific tube may land a little to one side.
How does the paint mixing quiz work?
There are 80 questions: 40 easy ones with two paints and 40 hard ones with three. Some use amounts, such as two parts yellow to one part blue. Each answer was checked against the mixing model, and combinations whose result sits between two color names were left out. Wrong options are always clearly different colors, so a careful guess can be reasoned out.