What color do red and grey make?
Red and Grey make rust.
Red and Grey make rust, #b34343. That is the result in equal parts, mixing pigment rather than light - paint, ink and dye all behave this way.
Equal parts red and grey · #b34343
Change the ratio
Very little of a mix is ever half and half. Shifting the balance moves the result along the range between the two colours.
3 parts red, 1 part grey · #d92929
Equal parts · #b34343
1 part red, 3 parts grey · #8c4f4f
Lighter and darker
With white added - a tint · #cc9999
With black added - a shade · #661a1a
Why it works
Pigment mixes subtractively: red paint absorbs the wavelengths it is not reflecting, grey absorbs its own set, and rust is what neither of them absorbed. This is why paint behaves differently from a screen, where light adds together instead.
Frequently asked questions
What color do red and grey make?
Red and Grey make rust, #b34343. Mixed in equal parts that is the result you get with paint, ink or any other pigment.
How do I make the result lighter or darker?
Add white for a tint - here that gives tan. Add black for a shade, which gives maroon. Add white a little at a time, because it takes far less than people expect to shift a mix.
What happens if I use more red than grey?
Three parts red to one part grey gives crimson. Reversing it to one part red and three parts grey gives brown instead.
Does this work the same way on a screen?
No. Screens mix light additively, so red and green light make yellow there. These results are subtractive - paint, ink, dye and pigment - which is what people mean when they ask what two colours make.