These colors exist underneath the “main” color and are the reason one gray looks more brown or green and another is more of a bluish gray. This is true for neutrals, wood stains and anything except the purest primary color (red, blue or yellow). Every color has either warm or cool undertones. The best color wall color for wood floors actually 

Warmer undertones are red, orange or yellow bases. These colors will pair well with creamy white, beiges or earthy tones. Even if the hue is different, the undertones are harmonious.

Similarly cool undertones include blue, green or true gray bases. These floors will look best will cool whites, soft grays and muted sages.

In general, you want to pair warm undertone wall colors with similar floors and vice versa. When the undertones on the wall clash with the undertones on the floor, it can create a jarring effect. An icy gray wall with a golden yellow floor will create an uncomfortable visual tension but would pair quite well with deep brown flooring with cool undertones. 

Contrast within the same undertones is the secret to starting to match the wall color to your floor color. If each surface in your home was the exact same color, it would feel flat and uninspiring. Contrast creates interest and dimension.

If your floors are dark, light colors offer a classic designer look. The dark floors provide a visual anchor, light walls such as off-white or pastels keep the space feeling open, airy and bright.

Conversely, dark colors for light floors are an excellent choice to create a dramatic or cozy space. The light bounces upwards, balancing out moody wall colors like charcoal, indigo or forest green.

You can still achieve a subtle contrast with a light wall and floor color combination, provided you select a different paint color than floor color and stick with the type of undertone. The effect is a modern, minimalist or Scandinavian vibe. 

The amount of sunlight a room receives significantly shifts how wall and floor colors interact. The more sunlight, the more the undertones of the paint show through. Lower light makes neutral paints look darker and less saturated, maybe even feeling “muddy.”

For small or dark rooms, ensure there isn’t too much heaviness. Select either dark floors or dark walls, not both. Otherwise, it creates a cave-like feeling. Instead, consider pairing light floors with bright white or creams to reflect the light you have.

If you have bright, sun-drenched rooms, this offers more freedom. Natural light softens darker colors and also pleasantly highlights the textures of stones, tiles and other surfaces. Light colors can also make these rooms feel breezy and airy, provided there isn’t so much light it gets overwhelming. 

If your walls and floors are very similar, transition pieces can visually separate them.

• Baseboards and Trim
  Crisp white or off-white baseboards act as a break between the wall and floor, preventing them from "bleeding" into one another.
  
• Rugs and Furniture
  A large area rug placed over a floor can help bridge a tricky color gap, allowing you to pull accent colors from the rug into your wall art or throw pillows.