It's all about reflecting light.

Benjamin Moore’s Cloud White (OC-967)
Credit: Laurey W. Glenn

Interior design is often about creating illusions and manipulating perspective. We know the tip about hanging curtains higher than the window to make ceilings appear taller, as well as the one about making sure your rug is properly sized for the room and the furniture sitting atop it.

And one of the most frequently cited tips to make a room feel and look bigger is by changing the paint color. Specifically, by painting the walls white. And while white is not always the best option for enlivening a small room (it's certainly not the only one), it will, 98 percent of the time, make the room feel brighter and more spacious.

As anyone who's picked out a shade of white paint knows, it's no small feat. Within any paint company, there are dozens if not hundreds of shades of white. There are warm whites, cool whites, whites with blue undertones, and whites with pink undertones. While it's true for any paint color, it's especially necessary to test white paint in the room it will be in to see how it reacts to the light and shape of the room—and how you react to it.

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To make your room look bigger, you want light to bounce off of the walls, not hit them and fall flat. Design professionals refer to a measurement called Light Reflectance Value (LRV) that defines the percentage of light reflected off a painted surface, on a scale of 1 to 100. 100 LRV would be pure white, which, as you might predict, is a bit too stark for anyone to live in. Leave that for the art galleries. But the closer your paint is to 100 LRV, the more light it will reflect, creating the illusion of a bigger, brighter space.

Our top pick for the white paint that will make your room look bigger? Benjamin Moore's Cloud White. It's a soft white that has warm undertones but a relatively high LRV of 87.35. When reflecting either natural or interior lighting, walls in this shade will bounce off brightness without looking sterile. To make your room feel even larger, it's helpful to paint any trim the same color as your walls. This is a great trick when using a more saturated color on the walls (so your eye doesn't stop at white trim when looking up) but works just as well with white paint, to create the appearance of one continuous surface.

Since there truly is no one color that will work in every space, it's good to have options. Other popular bright off-whites include Sherwin Williams Alabaster, Behr Off White, and Benjamin Moore shades White Dove, Acadia White, and Swiss Coffee. All have slightly different undertones (ranging from gray to green-brown and yellow) so again, it's important to test your white paint in a large portion of the room it will be going in.