Chrome's actual color picker widget has an eye dropper to let you pick any color. Chrome actually has an API to let you easily add that functionality https://developer.mozilla.org/en-US/docs/Web/API/EyeDropper - although it won't work in any other browsers, unfortunately. Might still be worth adding, you can do feature detection to decide whether to show it or not.
Chrome's actual color picker widget has an eye dropper to let you pick any color. Chrome actually has an API to let you easily add that functionality https://developer.mozilla.org/en-US/docs/Web/API/EyeDropper - although it won't work in any other browsers, unfortunately. Might still be worth adding, you can do feature detection to decide whether to show it or not.