VA Rating CalculatorVA math is not addition
Many veterans assume that a 50% rating plus a 30% rating equals 80%. It doesn't. The VA uses what's called “whole person” math from 38 CFR § 4.25. Each new disability is applied against the body's remaining efficiency, not against 100%.
The formula in 3 steps
- Sort your ratings from highest to lowest.
- Multiply the remaining efficiency by
(1 − rating / 100)for each rating. - Subtract from 100, then round to the nearest 10%.
Worked example: 50% + 30% + 20%
- Start at 100% efficiency.
- Apply 50%: 100 × 0.50 = 50% remaining.
- Apply 30%: 50 × 0.70 = 35% remaining.
- Apply 20%: 35 × 0.80 = 28% remaining.
- Combined disability = 100 − 28 = 72%.
- Round to nearest 10 → 70% VA rating.
Why the order doesn't matter
Multiplication is commutative, so combining in any order produces the same result. The VA sorts highest first only for clarity in their published combined ratings table.
What about the bilateral factor?
If you have disabilities affecting paired limbs (both knees, both arms), the VA adds a 10% bilateral factor before combining with your other ratings. See Bilateral Factor Explained.