We have all read about monochromatic color schemes meaning that the room or object is designed with the same color from light to dark all around the item. But, as a practical matter, what does monochromatic mean? One of the easiest ways to understand monochromatic is to take a paint color chip with the 5 colors on it, and use all 5 colors all around a room.
Usually but not always, the floor is the darkest, then the walls and furniture the medium shades and the trim is the very lightest color. The most interesting monochromatic rooms have darker and lighter versions against each other all over the room. Here are some examples.
I'll begin with this brown monochromatic bedroom because it is the most commonly used bedroom color in residential homes. In this case the neutral color is the main color for the room, and that is a true tan leading into very dark brown and has very light browns against it. This bedroom inverts the usual color scheme to make the walls dark and the floor lighter, and is a very effective color scheme for bedrooms.
This was a color test for a few things so the lamps don't match and the floor is a bit too red. But, about half of residential living rooms have the monochromatic light to dark brown color scheme, because when you go furniture shopping, the most common sofa color is brown. The area rug has all kinds of shades of light to dark tans and the sofas are an exact match to the rug. The wall and trim paint color, and everything else is from light to dark all around the room, and the more contrasty it is the better it looks. Thing is that when you go shopping for tans, you will find out fast that you have to match the exact shades of tan, that they are not too yellow or too red.
This room is monochromatic fuscia leading into it's lighter version which is pink, and the neutral is white, and it's very tricky to put together all those patterns. The floor is the darkest solid color, and the bedspread has more variation in pattern but matches the carpet color nearly exactly, and the walls as they go higher get lighter. In all rooms, there is a neutral color which in this case is white, and one of the 6 colors on the color wheel. So your room will start out with the lightest value of the neutral, and then get darker into your choice of color, so just because there is neutral showing in the room, it's still monochromatic. This room has the advantage of having green leaves in the patterns which gives it a minor amount of accent color. How light you go as you go up the walls is up to you.
This bedroom is a very light pastel earth tone peach, it's a creamy peach. This website is to help you see the minor differences in colors, and to automatically be able to see the composition of each color, as they all have an undertone, and the undertone of this color is cream, everything in the room is a pastel earth tone. The carpet is the most solid and darkest value, the bedspread is so close a match to the floor it looks stuck to it. Then there is a painted lower wall, and the wallpaper above is a mixture of cream and peach making the room lighter above. You can argue that there is some complimentary blue accent color so it is not absolutely monochromatic. But, even the woods and everything blend right into each other with very slightly lighter and slightly darker values all throughout the room.
A monochromatic blue kitchen deriving it's colors from the glass tile back splash. This room has a lot of white neutral in it, plus about 4 shades of the same color blue. It would be even more interesting with contrasting light blue tiles forming a pattern in the floor.
A dark blue living room in blue monochromatic with lots of shades of clear blues all around the room. The neutral is dark gray leading into black. You have to see the neutral base undertone of the color samples to make the room because the neutral does show up in small or even large doses all around the room. The carpet is navy blue with a black undertone, the wall paint color is a medium blue with a slight gray undertone, this is a very common and very effective color scheme where the floor is dark, and the walls are a gray tone which keeps the room medium light. Then the various patterns go back and forth from light to dark all around the room in the same color, but the neutrals show up as well.
Well, this room has the yellow accent chair, but other than that it's a very good example of monochromatic in purple bedroom. The neutral is white. The floor is very dark purple. The bedspread contains several shades of medium purple including a stripe and floral which is a standard decorator pattern mix. The lower wall is painted medium purple, and the wallpaper on the upper wall mixes the neutral white with a lighter shade of purple.
How dark or light you go in each area is up to you, but the more you place the darker and lighter elements against each other, and the more that the neutral color is weaved into it in small doses, the better it looks.