Unfortunately, there's no rule. There's just an understanding of the effects you'll get in your particular room with different tints and shades of color.

("Tint," by the way, refers to a lightened/whitened version of a color, and "shade" refers to a darkened/blackened version.)

I think your first step is to start looking at pictures in magazines and on Houzz, and really think about how you feel about different choices - for instance, you can search Houzz for "deep bedroom walls" and "medium bedroom walls" to see a variety of shades, some of them matched with curtains.

Thank you for the suggestion to check Houzz!

I wish there was a rule, darnit ;-) I feel more relaxed with there is lower contrast between colors, so my gut is telling me to go with medium!

I think you should consider your room's feel-- do you like the cavelike feeling? Is it something that could be changed with a lighter color? Would you want it to?

And I agree-- if you don't like high contrast, a medium value would be best.

I picked out medium colors recently for my dark rooms. One of the things I like is that my blue has energy in it even when the lights are off. I can still see a color when it's dark. . .but, with the lights on, somehow it is still fairly muted.

Let me know if you find a caramel color that works. I wanted caramel, too, but didn't have much time to test and was worried about a greenish undertone.

In a space that is not flooded with natural light, I like at least one element in the room - either floor, walls, furniture or drapes - to be at least a couple of shades darker or lighter than everything else. The darker or lighter color makes the other colors look like more of what they are. Otherwise you can end up with a room where it's hard to perceive any color at all, because subtle color differences don't show in dark places.

Are your carmel drapes darker or lighter than the teak or about the same?

What color are the floors?

For example, if the drapes are about as light as the teak, and the floors are medium brown as well, then I think I'd go a few shades lighter for the walls.

If the drapes are lighter than the teak, I might go with a darker-than teak wall color.

anele -- I doubt a light color will make it feel any brighter, it's currently semi-gloss white! I think it feels stark and depressing.

I like light and bright, but cozy would be okay since I don't think light and bright is really possible with just changing the paint. It's a small room, our home is small, so I would be happy with a cozy feel!

I don't really like greenish undertones, either!

jamies -- I appreciate your comments about choosing a shade depending on how dark the other things are in the room, that is very helpful! The curtains are a little lighter than the teak; they aren't similar colors (the curtains have more gold and the teak more brown/orange).

The floors are definitely light, sort of an oatmeal color carpet. If we ever changed the flooring, I would not pick anything darker.

I did paint our master bath a medium shade of grey, and I love it. It feels really right, not too intense, and not lackluster. Maybe I should try for a shade about the same in value? That way the change in color will be somewhat muted by them having similar value?

Have you considered the color choice of the bedrom with the bed that you showed?

Here is a link that might be useful: bedroom with teak bed

nosoccermom --

I think the bedroom w/the bed I showed looks really nice, but seems to have a lot more light in it than our room. The room looks really fresh and bright! Our room, even with white walls, doesn't have a bright feel except around noon-ish (when a lot of sun is coming through the window). I do like it at that time, but I want to like the room ALL the time ;-)

I like the first photo you posted, where the wall color is similar to the curtains but a bit darker. That's what I'm leaning toward, slightly darker than the curtains.

I really appreciate everyone helping me think this through!

You said your curtains are caramel, but are they darker than in the first picture? A lot will also depend son your bedding and wall decoration.
Also, I find that white in a room with less light will look more dingy than a beige, oatmeal or greige.
Can you post a picture of your bedroom?

We don't have any wall decoration, the bed is right under a large window. My DH has a SF Giants calendar on his side, does that count LOL?

Our bedding is dark blue, although I do have a set of light green. The curtains are darker that your picture, they look kind of like these (and my furniture seems similar to the flooring in this pic). I do not like the light walls in this photo, which also makes me think I should choose a medium shade:

I love the first color of the wall posted by nosoccer mom-- it is darker than the one you posted of the curtains (which I also love!).

I think it would be OK to match the curtains, but I would prefer a bit of contrast between the wall and bed.

What is your flooring like? If HW, do you have a rug?

Could you take the curtains and match the paint and then go a little lighter, and maybe get duvet covers at IKEA or West Elm for a quick bedding change. I love IKEAs satiny cotton duvets and sheets.
Maybe even this:

I have these in turquoise and in a blue/green/purple pattern.

anele -- yes the first pic is beautiful! To get more contrast between wall and bed, the wall color would need to be lighter than the curtains.

The flooring is carpet, oatmeal color. If we update the flooring, I would choose something similar for our bedroom.

Nosoccermom -- I like your idea to match the curtains but go a bit lighter. I was initially thinking to go a little darker, but I think going a bit lighter will help the curtains/window/bed stand out a bit more, without being too high contrast, and not making the room feel excessively dark.

I hadn't considered changing our bedding, I like the blue a lot -- it's sort of a medium slate/navy. I don't like our light green set as much; if I change that, I will probably go with white. The set in your picture is cute, but is kind of busy to me. I prefer solids, or tone-on-tone print/stripes. Our curtains have a floral/paisly type of texture on them, but it's subtle.

I was trying to visualize a beige that would go with grey, and also has brown (like the teak) and white/off-white (floor), so remembered these sheets. Looking at the sheets as a possible combination of colors, i.e. color board, navy looks like it would go well (the navy instead of the turquoise). And white sheets would be very nice.

RE: your rug-- I think the undertones of it will guide you to your paint choice.

I like the idea of it being a little lighter than the curtains.

Nosoccermom, I like the duvet set you posted!