Type “what color does red and green make” into a search box and you will find two confident answers that flatly disagree. One set of pages says brown. Another set says yellow. Neither is wrong. They are answering for two different kinds of mixing, and almost nobody tells you which one they mean. That single missing detail is why color mixing feels slippery long after you have memorised the color wheel.
There are two ways to combine colors, and they run in opposite directions. Mixing paint, ink, or any physical pigment is subtractive. Mixing light, which is what every phone, monitor, and television does, is additive. Pick the wrong model and your answer for the same two colors flips. This piece sorts both out, gives you a clean reference for the pairs people actually look up, and explains why red and green is the one that catches everyone.
Why there are two answers, not one
A red apple looks red because it soaks up most of the light that hits it and bounces only the red part back to your eye. Pigment works by taking wavelengths away. Stack a second pigment on top and it removes more, so the result is always darker than either color you started with. Mix enough pigments and you head toward a muddy near-black, because between them they have subtracted almost everything. That is subtractive mixing, and it is what you were taught with paints in school.
Light does the reverse. A screen makes color by switching on tiny red, green, and blue emitters and letting them add together inside your eye. Each color you add puts more light in, so the result is always brighter than either source. Add red, green, and blue light at full strength and you get white, the exact opposite of the paint result. James Clerk Maxwell proved this in 1861 when he built the first durable color photograph out of three separate red, green, and blue exposures projected back on top of each other (Royal Museums Greenwich).
So the honest answer to “what color do two colors make” is always a question back: are you mixing stuff or mixing light? Hold that and the contradictions disappear.
The paint answer: subtractive mixing
This is the model behind the classic artist’s color wheel, built on red, yellow, and blue as primaries. Combine two of them and you get a secondary color. Combine a primary with a secondary and you get the in-between tertiary shades like teal and chartreuse. These are the results people expect when they think of mixing paint, and they hold well enough for school poster paint and colored pencils.
| Red + yellow | Orange |
| Yellow + blue | Green |
| Red + blue | Purple or violet |
| Blue + green | Teal, a blue-leaning cyan |
| Red + green | Brown, a muddy dark |
| Yellow + green | Lime or chartreuse |
| Pink + blue | A soft purple or lavender |
| Red + white | Pink |
| Any color + black | A darker, duller version of itself |
The standout is red and green make brown. Red and green sit opposite each other on the wheel, so they are complementaries. Mixing complementary pigments cancels them toward a neutral, and because you are subtracting from both sides at once, that neutral lands as a dull brown rather than a clean grey. Painters use this on purpose to knock the life out of a color that looks too garish.
One honest caveat. Red, yellow, and blue are a teaching convenience, not the primaries real printers use. Color printing runs on cyan, magenta, and yellow because that trio can subtract its way to a far wider range of colors than red and blue can. The red-yellow-blue wheel gets the everyday answers right, but if you have ever wondered why printer ink is labelled CMYK rather than RYB, that is why.
The screen answer: additive mixing
Now the same pairs, mixed as light. Here the primaries are red, green, and blue, the three colors your screen actually emits. This is the model that matters for anything on a display, including the color in this game, and it is where the answers stop matching the paint chart.
| Red + green | Yellow |
| Green + blue | Cyan |
| Red + blue | Magenta |
| Red + green + blue | White |
| Blue + yellow light | A washed-out white, not green |
Red and green light make yellow. This is the result that breaks people’s intuition, because it is the exact opposite of the brown you get with paint. There is nothing exotic happening. Your eye has separate red-sensitive and green-sensitive cone cells, and firing both at once is the same signal it receives from genuine yellow light around 580 nanometres. The screen never produces a yellow wavelength at all. It fakes the sensation by triggering two cone types together, and your brain reports yellow. The whole of color on a display is this trick repeated millions of times, which the how many colors can you see piece picks apart in more detail.
Notice the blue-and-yellow line too. In paint, blue and yellow make green, one of the first rules anyone learns. In light, yellow is itself red plus green, so blue plus yellow light is really blue plus red plus green, which is all three primaries, which is white. Same two color names, opposite outcome, purely because of which kind of mixing you chose.
Where the two models actually collide
Most pairs people search for are not pure light primaries. Pink, orange, brown, and teal are not colors a screen emits directly, so the question “what does orange and pink make” is really a paint question even when you are staring at a monitor. For those, use the pigment chart. The additive rules only take over for the three light primaries and the secondaries they build. Here is the short list of pairs where the two models genuinely disagree, which is worth knowing because these are the answers that start arguments:
- Red + green: brown in paint, yellow in light.
- Blue + yellow: green in paint, near-white in light.
- Red + blue: purple in paint, magenta in light. Close cousins, but magenta is pinker and brighter than mixed-paint violet.
Everywhere else the two systems roughly agree, or the pair only makes sense in one of them. That is the practical takeaway. You do not need to memorise two full wheels, only the three places they part ways.
Feel it with the sliders
Reading the rule is one thing. Watching red and green climb into yellow in front of you makes it stick. The Color Mixer in this game gives you three sliders, one each for red, green, and blue light, and a target color to hit. Push red and green up together with blue at zero and the swatch turns yellow, not brown. Add blue and it walks toward white. You are driving the additive model by hand, the same red-green-blue mix your screen runs on every second.
From there it is a short step to reading those mixes as numbers. Every color on a screen is just an amount of red, green, and blue written as a hex code, and pure yellow being ffff00, full red plus full green plus no blue, is the same fact this article started with, written in the notation your browser uses. The reason a flat mixing rule can feel unreliable in the real world is color constancy, your brain quietly correcting for the light in the room so that the same mix can look like two different colors depending on where you see it.
So the next time someone asks what two colors make, the useful reply is not a single shade. It is one question. Paint or light? Answer that and every entry on both charts above falls into place.