Today’s Question: When I’m adding text to an image that I’ll be sharing online, I’ve noticed the “Only Web Colors” checkbox. Do I need to turn this on when selecting a color for an image I’ll share online?
Tim’s Quick Answer: No, the concept of using “web safe” colors is largely outdated, and not an issue you need to be concerned about with today’s web browsers. When selecting colors in the Color Picker dialog, you can therefore leave the “Only Web Colors” checkbox turned off.
More Detail: In the early days of the World Wide Web, web browsers (and in many cases the computers being used for browsing) were not able to display a particularly large number of colors. As a result, the notion of “web safe colors” was developed.
Because only a limited number of colors could be presented by certain hardware when the World Wide Web was first developed, it was important to use “web safe” colors when creating a web page in order to ensure the colors could be presented accurately.
Originally, there were only sixteen colors defined as standard “web safe colors”. You could certainly employ colors beyond that number if you wanted to, but the appearance of the colors would not always be accurate depending on the capabilities of the computer (and web browser) being used to present the page. The number increased to 216 colors later, but now this concept can generally be ignored.
The vast majority of computer systems and other devices used to browse the web can present 8-bit per channel color (or better). Therefore, it is not necessary to limit yourself to only the “web safe” colors when selecting a color to use in an image or graphic that will be published online.
In other words, at this point there is no need to worry about the concept of “web safe” colors. I do, however, recommend embedding a color profile (preferably using sRGB) for photos that will be displayed online, in order to help increase the potential for the most accurate presentation possible for the image.