First, install Hex Color Picker by Waffle software. It will add an extra option to the built-in OSX color picker to show you the selected color in Hex.
To reach the color picker, you usually start up any application which uses the standard OSX color picker and just choose “choose color”. What you can also do, is have the OSX color picker behave as a standalone application in 3 simple steps:
- Open “ScriptEditor”, the Applescript editor.
- In the main window, type “choose color”
- Save the script as an application.
The saved application will, you guessed it, show you the standard color picker. Add it to the dock and you will be a happy developer.
Please note: If you are really being a perfectionist, it is possible this will not work for you because the color profiles of you monitor and possibly the profiles which are applied by Safari will introduce errors, because the color picker shows you the color which is on the screen, not the original color coming from the application. There’s a whole slew of documentation on color profiles and I do have a whole rant which I will save you from reading (for now).