Coastal Grey vs Sleepy Blue
Coastal Grey is a Dulux color while Sleepy Blue comes from Sherwin-Williams. Hue-wise, Coastal Grey belongs to the blue-grey family and Sleepy Blue to the blue family. With LRVs of 56 and 58, they'll behave almost identically in terms of how much light they reflect back into a room. They share a cool quality — useful to know if you're layering them in the same space. With a ΔE of 1.8, the difference is subtle — you'd need them side by side to reliably tell them apart. Below you'll find 1 real-room photo comparison where both colors appear side by side, plus 5 simulated room previews.
Coastal Grey vs Sleepy Blue in Real Spaces
1 real room side by side. Coastal Grey and Sleepy Blue are close enough that the difference can be hard to judge from a chip alone — these photos show how each reads at scale, across different spaces and lighting conditions.
Bathroom
Bathrooms amplify color — the enclosed space and reflective surfaces make what reads subtle elsewhere feel more present here. The two are close enough that the choice comes down to finer qualities — undertone, texture, what the color sits next to.
Color Details
Coastal Grey vs Sleepy Blue Simulated Comparison
5 simulated room previews — drag the slider on each to see Coastal Grey on one side and Sleepy Blue on the other.
Digital color is approximate. These simulations are generated from the manufacturer's hex values and overlaid on grayscale room photos — your screen's calibration, brightness, and viewing angle all affect how they render. Before committing to either color, test physical samples in your own space under the light you actually live with.
More Coastal Grey comparisons
See how Coastal Grey stacks up against other well-photographed colors across different brands and tones.
