What Color Does Red and Blue Make? Color Mixing Guide
What Color Does Red and Blue Make?
Purple. That's the straightforward answer. When you mix red and blue together, you get purple or violet, depending on the exact shades and ratios you use.
But if you're here, you probably want more than just the answer. You want to understand why, how to get different shades, and where this actually matters. Let's break it down.
The Basic Science Behind Red + Blue = Purple
Colors aren't magic. They're wavelengths of light bouncing off surfaces and hitting your eyeballs. Red light has the longest visible wavelength (around 700 nanometers). Blue sits on the opposite end with shorter wavelengths (around 450 nm). When you mix pigments, you're essentially combining molecules that absorb certain wavelengths and reflect others.
Red absorbs green and blue. Blue absorbs red and green. When you combine them, they cancel out those middle wavelengths, leaving you with something that sits between them on the color spectrum. That's purple.
Additive vs. Subtractive Color Mixing
Here's where people get confused. There are two ways to mix colors, and they give different results.
Additive Color (Light)
This is how screens work. Red light + Blue light = Magenta. Your phone, TV, and computer monitor use this system. RGB (Red, Green, Blue) is the additive model.
In additive mixing:
- Red + Blue = Magenta (a purplish-pink)
- Red + Green = Yellow
- Green + Blue = Cyan
Subtractive Color (Pigments)
This is how paint and printers work. When you mix pigments, you're subtracting wavelengths from white light. CMYK (Cyan, Magenta, Yellow, Black) is the subtractive model used in printing.
In subtractive mixing:
- Red + Blue = Purple or Violet
- Red + Yellow = Orange
- Blue + Yellow = Green
Most people asking "what color does red and blue make" are thinking about paint, crayons, or digital art. That's subtractive mixing, and the answer is definitely purple.
Shades of Purple You Can Create
The exact shade you get depends on your ratios and the specific reds and blues you're starting with.
| Ratio (Red : Blue) | Resulting Color | Best Used For |
|---|---|---|
| 1:1 | Medium Purple | General artwork, backgrounds |
| 2:1 (more red) | Reddish-Purple (Magenta-ish) | Shadows, depth, skin tone undertones |
| 1:2 (more blue) | Blue-Violet | Cooler tones, night scenes |
| 3:1 (mostly red) | Rose/Mauve | Flesh tones, warm purples |
| 1:3 (mostly blue) | Deep Indigo | Dark accents, navy transitions |
The ratios above assume you're working with primary red and primary blue. If you're using premixed colors or ones with existing undertones, your results will vary.
Real-World Applications
Knowing how to mix red and blue into purple actually matters in several fields:
- Painting and art: You don't need to buy purple paint. Mix it yourself and save money. Plus, you get more control over the exact shade.
- Interior design: Creating custom wall colors or understanding how furniture and decor will look together requires knowing color relationships.
- Digital design: Understanding hex codes and RGB values means you can create any purple you want in Photoshop, Illustrator, or web design.
- Print design: CMYK values for purple are different from RGB. Getting the right shade for print versus screen requires knowing the difference.
Common Mistakes to Avoid
People mess this up constantly. Here's what not to do:
- Using too much medium: Adding white or black to "lighten" or "darken" purple is fine, but adding too much changes the color entirely. A little goes a long way.
- Ignoring undertone: Some reds lean orange. Some blues lean green. These undertones affect your final purple. Test small amounts first.
- Assuming all reds and blues are equal: Cadmium red and alizarin crimson are both "red" but give completely different purples. Same with ultramarine versus cobalt blue.
How to Get Specific Purple Shades
Violet (Light Purple)
Start with blue, add a tiny bit of red, then mix in white until you hit your target lightness. Violet is cooler and more blue than purple.
Magenta (Pink-Purple)
Lean toward red, add just a hint of blue. This is closer to what you'd get with additive mixing. Magenta is warmer and more vibrant.
Deep Royal Purple
Mix equal parts red and blue, then add a very small amount of black to deepen it. Don't overdo the black or you'll get muddy brown-purple.
Lavender (Light, Muted Purple)
Start with white as your base, add blue, then introduce red gradually. Keep adding white to maintain lightness. Lavender needs more white than you think.
The Bottom Line
Red and blue make purple. That's the whole answer. The variations come from ratios, specific pigment choices, and whether you're working with light or pigment.
If you're mixing paint, use roughly equal parts and adjust from there based on what you're seeing. If you're working digitally, red (#FF0000) + blue (#0000FF) gives you purple (#800080) in RGB.
Stop overcomplicating it. Mix, test, adjust. That's color mixing.