I found this amazing tool today: The ColorZilla developer add-on tool for Firefox. If you’re a web developer, and like browser F12 tools, you’ll love this. It has an Eyedropper tool that lets you easily get the color of anything in the browser window, then automatically copies it to your clipboard.
There are plenty of other features too, such as a color palette browser, and a webpage DOM color analyzer, which its pretty cool. It extracts all the colors for the page in your current tab.
My advice? Definitely worth installing!