For many veterans, a VA disability rating is more than a number. It affects monthly income, health care access, and long-term planning for a household. Yet the system that produces that number can feel confusing, especially because ratings are not simply added together. A VA rating tool, which estimates a combined rating from a list of individual ratings, can bring clarity to that process and help veterans plan with more confidence. Understanding what these tools do, and what they cannot do, makes them far more useful.