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VA Benefits

VA Combined Ratings Calculator: How VA Math Works (2026 Guide)

The VA doesn’t add your disability ratings — they use “VA Math.” Learn why 70% + 30% = 79%, how rounding works, and how to calculate your monthly compensation.

3 min read

February 8, 2026

By VA Rating Assistant Team

If you have multiple service-connected disabilities, you’ve probably noticed something strange: the VA doesn’t simply add your ratings together. A veteran with 70% PTSD + 30% knee injury doesn’t get 100% — they get 79%, which rounds to 80%.

Welcome to VA Math — the combined ratings formula that confuses nearly every veteran filing for disability.

Why the VA doesn’t just add your ratings

The VA uses the “whole person theory”: you can’t be more than 100% disabled. Each additional rating applies to what’s left of your “remaining capacity.”

The combined ratings formula (simple version)

New Total = Current Total + (New Rating × Remaining Capacity ÷ 100)

Example:

  • Current: 70% → Remaining capacity: 30%
  • Add 30%: 70 + (30 × 30 ÷ 100) = 79%
  • Round at the end: 79% → 80%

Rounding rule (critical)

  • 0–4 rounds down
  • 5–9 rounds up

So 84% pays at 80%, but 85% pays at 90%.

Bilateral factor (both arms or both legs)

If you have disabilities affecting paired limbs, the VA may apply a bilateral factor before combining with other ratings.

Next steps


Calculate your combined rating

If you have multiple conditions, our calculator shows your combined rating and monthly compensation using the VA's formula.

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Upload your medical records and get an AI-powered rating estimate in minutes. We'll help you find evidence gaps and next steps.

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