Paint and primer: What’s the difference and why does it matter?

Oh, jeez, here we go again. The difference between primer and paint.

There’s so much misinformation circulating, it’s hard to determine who’s right and who’s wrong. Some say priming isn’t necessary. Some say there’s no difference, that primer is a kind of paint. (WRONG!) Some say you can use old paint as a primer. (Also WRONG!)

There absolutely is a difference between primer and paint. The ancient Egyptians knew it, the Italian Renaissance painters knew it, and now you’ll know it.

Paint and primer have different ingredients

Paint and primer were made for two different purposes. Of course they would contain different ingredients. You wouldn’t use silly putty in a Play-Doh Barber Shop, would you?

Silly Putty is far less pliable and would clog up the holes in your Barber Shop. Play-Doh is designed to be soft enough to push through those holes so you can cut it with plastic scissors into the worst mullet you can imagine.

Primer and paint are like silly putty and Play-Doh. They have different physical properties because they’re designed to accomplish different tasks.

What primer and paint are made of

There are a few differences in formulation, but some ingredients are the same.

Primer contains:

  • Resin. The “binder” that binds pigment particles to the dried film. In latex paint, the binder is usually vinyl acrylic, polyvinyl acrylic, or styrene acrylic. For our purposes, a binder is just a material that the pigment particles can “hang out” in until they get close together enough to crosslink.
  • Limestone. It’s not just an extender — it’s really a color-neutral way to add body and texture to the primer.
  • Titanium dioxide. An opaque, lightfast, and bright white pigment.
  • Additives. To handle things like frothing, clumping, and separating.
  • Vehicle. The fluid part of paint — solvent combined with resin. In latex paint, this would be water and vinyl acrylic.

Paint contains:

  • Pigment. The ingredient that gives paint its color. Pigments are mined or manufactured, processed, and ground to extremely fine particles before being added to paint.
  • May or may not contain titanium dioxide. TiO2 is a white pigment and an opacifier, meaning it’s very opaque and mixes with other pigments in a way that increases their opacity.
  • Vehicle

Paints don’t contain limestone. They don’t need to because they aren’t meant to provide body or texture on their own.

Whether or not they contain titanium dioxide (PW 6) depends on how light or opaque they are, or what pigments are necessary to mix the color.

Paint and primer are made for different purposes

Paint was invented thousands of years before primer. Paint used in caves definitely predates 11th century Egyptians and 14th century Italian Renaissance artists.

So, if people have been painting surfaces for thousands of years, why was gesso invented in the first place? Weren’t painters getting along just fine without it?

Gesso was — and still is — the primer used by oil painters to prime their canvases, wood panels, and other substrates before painting.

The primers you use to prepare your walls before you paint serves the same purpose. To seal the surface you’re painting to prevent over-absorption of the more expensive pigmented paint you’re painting with.

Do I really need to prime before I paint?

I don’t know.

Do you want to:

  • Spend too much time and money on paint because it soaks into the wall and requires two or three additional coats?
  • Over-spend on paint because it takes several coats to cover stains?
  • Throw your cash away to repaint because the color you applied never formed a stain-resistant finish?

Then painting without priming first is for you.

But if you have better things to do and spend your hard-earned scratch on, here’s why you should prime first.

Yes, you need to prime before you paint!

Sometimes the easiest of what you hear is wrong.

If you paint without priming first, woe befalls you:

  • You’ll throw away good money after bad by repeating this step too many times. Primer is made to seal an overly-absorbant ground (like drywall) so that you don’t waste paint on it.
  • Your paint job will be compromised long before you’re ready to paint again. You don’t want to spend all that time taping and painting, and now you have to do it again a few years later because the paint is peeling.
  • Forget about covering stains. They’ll show up again. Especially if anyone in your household has an affinity for Sharpies or spaghetti sauce.

Priming first guarantees you the best coverage and the ideal ground to accept paint layers. The paint you apply will adhere well to a primer. It has plenty of texture to adhere to.

That’s a no-brainer, isn’t it?

Important: If you’re using latex paint, apply a latex primer first. Applying latex over an oil-based primer will cause the paint to peel.

What about paint and primer in one?

Paint and primer in one is fine if you’re painting over a similar paint color. Usually.

Not useful for first-time paint applications. If you’re looking at raw drywall or wood, forget it.

Remember that any porous surface will absorb too much water from the paint and ask yourself if an opacifier will stop this. It won’t. That’s not the function of an opacifier.

Painting and priming serve different purposes and are formulated accordingly.


  1. Prime before you paint.
  2. Use a latex primer under latex paint.
  3. That’s it.

How to use a color wheel to choose a harmonious color scheme

Are you tired of looking at your walls? Maybe it’s time to repaint a room or two in your home. Choosing new colors and repainting your walls can make your home feel like an entirely new place. And it’s a relatively inexpensive way of setting yourself up for a new state of mind. If only you could figure out which colors would go well together.

If you don’t trust yourself with color decisions, choosing a color scheme for your rooms can seem like more work than actually painting. Don’t forget, though, that color experts have been working on these issues for centuries. You don’t need to figure it out for yourself — artistic and scientific people have done that for you by inventing the color wheel to show color relationships.

What is a color wheel?

A color wheel is a tool that artists have been using for centuries to choose colors for their paintings. Munsell Color credits Sir Isaac Newton with inventing the first color wheel in 1704. His studies of light refracted through a prism proved that colors have relationships to each other, and those relationships determine how our eyes perceive them when they’re next to each other.

Our eyes are capable of perceiving a range of light that is created by wavelengths from 380 – 700nm. Light that travels at wavelengths in that range is received by our eyes and translated into a spectrum of color ranging from violet to red.

The wheel shows samples of each category of the spectrum of light visible to human eyes. You might notice how colors next to each other appear related. It’s no coincidence that the arrangement of these colors on the wheel follows the same progression of color gradations in a prism spectrum or rainbow.

They are all arranged in relation to the three primary colors — colors that cannot be replicated by mixing other colors together.

A few basics of color theory that will help you make a decision

Primary colors

Primary colors red, yellow and blue, are equidistant from each other on the color wheel.

The three primary colors are red, yellow and blue. All other colors are made by mixing these colors together in various proportions. Mixing any two of these will produce what’s called a secondary color.

Secondary colors

Secondary colors orange, violet and green, are made by mixing two primary colors.

Secondary colors are those three colors made by mixing two of the primary colors together. Orange is made by mixing red and yellow. Green is made by mixing yellow and blue. And purple – you guessed it – is made by mixing blue and red.

How to choose aesthetically pleasing color schemes by understanding color relationships

Complementary colors

Complementary colors are two colors that appear opposite each other on the color wheel. Such pairings include red and green, blue and orange, and yellow and purple.

Note that the color opposite a primary color is always a secondary color. The important thing to remember about complementary colors is that they complement each other because of their contrast.

For example, green is the complement of red because it’s a secondary color that contains blue and yellow (the other two primary colors) but doesn’t contain red. Orange is the complement of blue because it has no blue in it. Placing complementary colors next to each other makes them appear more brilliant because each one in the pair has something the other lacks.

Being next to blue makes orange look more intense.

Split-complementary colors

A split-complementary color scheme involves three colors, two of which are adjacent to the opposite color on the wheel from the first. For example, red’s split complementaries would be blue-green and yellow-green.

Orange with its split complementaries, blue-green and blue-violet.

Orange’s split complementaries would be blue-green and blue-violet. Because both colors are mixes of blue, they each offer an opportunity for different but related interactions with orange.

Analogous colors

This is another three-color scheme that consists of three colors next to each other on the wheel. For example, if you chose blue as a color to build a palette around, you would choose blue-green and blue-violet as analogous colors to go with it.

Analogous colors blue-green, blue, and blue-violet.

The color wheel shows you not just colors at their pure hue, but also their tints, tones and shades.

What are tints, tones and shades?

Each of these are made from a mixture of the pure hue in turn with white, gray, and black. To lighten a hue, you add white. Mixing a hue with gray makes it duller but doesn’t necessarily change the value (make it lighter or darker). Mixing the hue with black will darken it.

All three types of mixes will desaturate the color. You can see from the windows in the wheel what the effect on each hue will be.

Here’s a video that will walk you through basic use of the color wheel.