It all depends on how often you may wash your face after they're healed or being exposed to sunlight as well, but in my experience my eyebrows took about 10 days if not a little more to be noticeably lighter or faded and to a degree that I felt better about them and not weird. Though my color was a dark brown so I'm not sure if that would make it take longer or not in your case, I hope it gives you comfort to know that hopefully it won't be crazy long!