What Does Red and Blue Make? Every Result Explained by a Designer

Red and blue make purple -- but that single answer misses most of what actually matters. The exact shade of purple you get depends on the ratio of red to blue, the specific red and blue you start with, and whether you are mixing paint, light, or pigment. Get the ratio wrong and you end up with burgundy, magenta, or a muddy near-navy instead of the purple you wanted.

This guide covers every result -- what purple you get from different ratios, why the specific red and blue matter, how to control the result, and which paint colours sit in this range if you want to skip the mixing entirely.

The Simple Answer: Red + Blue = Purple

When you mix red and blue together you get purple -- a secondary colour that sits between red and blue on the colour wheel. Purple is neither warm nor cool on its own -- it sits at the boundary between the warm side of the colour wheel (reds) and the cool side (blues). The exact position of that purple on the spectrum -- how warm, how cool, how deep, how bright -- is determined by the ratio and by the specific red and blue you use.

What You Get at Different Ratios

Red + Blue ratio	Result	Character
Equal parts (1:1)	Pure purple / violet	Balanced -- neither warm nor cool
More red than blue (2:1)	Red-purple / magenta-purple	Warmer, more towards red-violet
More blue than red (1:2)	Blue-purple / violet	Cooler, deeper, more towards indigo
Red + small amount blue	Deep burgundy-purple	Very warm, rich, wine-like
Blue + small amount red	Deep indigo-purple	Cool, deep, close to navy

Why the Specific Red and Blue Matter

Not all reds and blues are the same, and this is where most colour mixing confusion comes from. The red and blue you start with each have their own undertones -- and those undertones carry through into the purple you create.

Warm Reds vs Cool Reds

Warm reds lean toward orange -- cadmium red, scarlet, vermillion. These contain yellow in their makeup. When you mix a warm red with blue, the yellow component interacts with the blue and can create a slightly muddy or muted purple rather than a clean one. For the cleanest, brightest purple, start with a cool red.

Cool reds lean toward blue -- crimson, alizarin crimson, quinacridone red. These already have a blue quality in their undertone. When you mix a cool red with blue, you get a cleaner, more vibrant purple because both colours are pulling in the same direction.

Warm Blues vs Cool Blues

Warm blues lean toward green -- cerulean, turquoise, phthalo blue. These contain yellow in their makeup. When you mix a warm blue with red, the yellow component creates a slightly muted, complex purple. For the cleanest result, avoid warm blues.

Cool blues lean toward violet -- ultramarine blue, cobalt blue, prussian blue. These already have a red-purple quality in their undertone. Mixed with red, cool blues create the clearest, most vibrant purples.

The Best Combination for Clean Purple

For the cleanest, most vibrant purple: use a cool red (crimson or alizarin) with a cool blue (ultramarine). Both colours lean toward each other on the colour wheel and the result is a clear, rich purple without muddy undertones. This is the combination professional artists and designers reach for when a clean purple is the goal.

How to Adjust the Result

Purple decor in a bedroom

To Make Purple Lighter

Add white -- this lightens the purple toward lavender or lilac. Adding white also slightly mutes the saturation, giving a softer, more pastel quality. For a brighter light purple without the muting effect, add a tiny amount of the lighter of the two original colours instead of white.

To Make Purple Darker

Add more blue -- this deepens the purple toward violet or indigo. Adding black will also darken it but tends to muddy the colour and reduce vibrancy. More blue is almost always the better route to a deeper purple.

To Make Purple Warmer

Add more red -- this pushes the purple toward red-violet, magenta-purple, or burgundy depending on how much red you add. A small addition of red warms the purple toward a plum or wine character.

To Make Purple Cooler

Add more blue -- this pushes the purple toward blue-violet or indigo. A predominantly blue mixture with a small amount of red creates the deep, cool indigo quality used in jewel tone colour schemes.

Red and Blue in Paint -- The Named Colours

If you want the purple family in paint without mixing from scratch, these are the most widely available and most used purple-family paint colours across the main brands:

Paint color	Brand	Character
Majestic Violet 2117-20	Benjamin Moore	Rich mid-purple, balanced warm-cool
Mystical Grape 2071-20	Benjamin Moore	Deep warm purple, red-violet direction
Plum Perfect SW 6545	Sherwin Williams	Deep, moody purple-plum
Signature SW 6815	Sherwin Williams	Muted mauve-purple, sophisticated
Passion Plum 2074-20	Benjamin Moore	Deep, rich burgundy-purple

Red and Blue in Interior Design

Purple decor in a bedroom

The purple family in interior design sits in the jewel tone category -- deep, rich, sophisticated colours that suit accent walls, cabinetry, front doors, and upholstery. The most widely used interior purples are deep and muted rather than bright and saturated -- they have enough grey or brown in the mix to prevent the colour reading as childish or garish.

Warm purples (more red) -- plum, aubergine, wine, burgundy-purple. These suit traditional, maximalist, and jewel tone interiors where warmth and richness are the brief.

Cool purples (more blue) -- indigo, violet, blue-purple. These suit contemporary, Japandi, and sophisticated interiors where a colour with depth but without warmth is the brief. Indigo sits at the extreme blue-dominant end of the red-blue spectrum -- for exactly where indigo lands and whether it reads as blue or purple in a real room, the is indigo blue or purple guide answers that directly.

Purple as an accent alongside neutrals -- purple accent colours work particularly well alongside warm greige neutrals, warm whites, and natural wood. The contrast between a warm-neutral room and a jewel-tone purple accent creates a layered, considered result that feels designed rather than simply coloured.

For the full breakdown of deep purple as an interior colour -- including paint recommendations and room applications -- the deep purple color guide covers everything you need.

Frequently Asked Questions

Purple decor in a bedroom

What colour does red and blue make?

Red and blue make purple -- specifically a secondary colour that sits between the two on the colour wheel. The exact shade of purple depends on the ratio of red to blue and the specific red and blue colours you start with.

Do red and blue make violet or purple?

Both violet and purple are the result of mixing red and blue -- the terms are often used interchangeably. Technically, violet is the cooler, more blue-dominant version while purple has more red in it. In practice, equal parts red and blue create something most people would call either purple or violet depending on the specific colours used. For a deeper look at where blue-purple sits as a colour in its own right, the blue purple color guide covers its character, undertones, and how designers use it in interiors."

What happens when you mix red and blue paint?

You get purple -- but the specific purple depends heavily on which red and blue you use. A cool red (crimson) mixed with a cool blue (ultramarine) creates a vibrant, clean purple. A warm red (scarlet) mixed with a warm blue (cerulean) can create a muddier, more muted result because both colours contain yellow in their undertones which neutralises some of the vibrancy.

Can you make purple from any red and blue?

Yes, but the result varies significantly. For the cleanest, most vibrant purple: cool red + cool blue. For a warmer, richer purple: more red than blue. For a deeper, cooler purple: more blue than red. For a muted, sophisticated purple: warm red + warm blue (the yellow in both mutes the result).

What does blue and red make in light?

In light (additive colour mixing) red and blue make magenta, not purple. Additive mixing is what screens and digital displays use -- red, green, and blue light combine to make white. Subtractive mixing (paint and pigment) is where red and blue make purple. The two systems work completely differently.

Final Thought

Red and blue always make purple -- but controlling which purple is entirely about ratio and colour selection. For a clean vibrant purple: cool red + cool blue in equal parts. For warmer plum or burgundy: more red. For cooler indigo or violet: more blue. For lighter lavender: add white. For deeper, richer purple: add more blue rather than black. Understanding these relationships gives you complete control over the result rather than hoping the mix turns out right.