Learn to mix colour

Colour theory for painters, tested in a real-pigment mixing model: what each paint does, and why mixes go wrong.

Why paint doesn’t mix like lightScreens add light; paint takes it away. Why blue and yellow paint make green, why red and blue can make black, and how this site mixes like real pigment.
Warm and cool colours, and why mixes go muddyEvery primary comes warm or cool. Which version you pick decides whether your oranges, greens and purples come out clean or muddy, with the numbers to prove it.
What white really does: tints, pastels and off-whitesWhite lightens, but it also cools and dulls. Why pastels need ratios like 40 to 1, why phthalo survives white and ultramarine doesn’t, and why off-whites take four paints.
Greys, neutrals and blacks without a tube of blackWhy painters mix greys from complements and blacks from colour, why tube black turns yellow olive, and the two-paint chromatic black.
Reds, pinks and purples: why purple goes brownWhy red and blue so often make mud, how to darken red without black, why white turns red pink, and which two tubes make every red, pink and purple.
Greens, blues and teals: why your green is dullWhich blue and which yellow make which green, why the ‘wrong’ blue gives you sage and olive for free, and how to darken blues without black.
Yellows, oranges, browns and goldWhy yellow turns olive when you darken it, how mustard and ochre are mixed with a violet, browns from three primaries, and how to paint gold without metallic paint.
Skin tones: one base, three valuesEvery skin tone from fair to deep, with recipes. Why skin is the hardest family to mix, why deep skin uses no white, and how to fix a mix that’s too orange, pink or grey.
Bright or muted: jewel tones and earth tonesIntensity is the third dial of colour, after hue and value. How to darken without dulling for jewel tones, and dull without darkening for earth tones.
Mother colours: palettes that hang togetherMix a little of one colour into every other and the palette reads as one light. How much to add, which mother to pick, and how to take a palette from a photo.
The six tubes that mix everythingThe split-primary palette: six colours and white mix every one of the library’s 193 colours. Which tubes do the most work, how to read a recipe, and why acrylic dries darker.