About
My VA Calculator exists because VA math doesn't work the way most people expect it to, and the official explanations don't make it any clearer.
The story
I'm a service-disabled veteran. When I got my combined rating, the numbers didn't add up the way I expected. Two conditions rated at 30% didn't equal 60%. My rating was lower than the sum of my parts, and nowhere could I find a clear explanation of why.
The VA publishes the rules in 38 CFR §4.25 and §4.26. They're legally precise and functionally opaque. If you know how to read the tables, you can work it out on paper. If you don't, you're left trusting that the number on your decision letter is correct.
I built this calculator first for myself, so I could verify my own rating. Then I realized other veterans probably had the same questions. So I made it free, put it online, and stripped out everything that wasn't useful: no ads, no email capture, no data collection. Just the math, shown honestly.
My VA Calculator is a project of Hudson Mohawk Web Studio, a small web studio I run in upstate New York.
How the math works
VA disability ratings don't add. They combine. This is the single most important thing to understand about how your rating is calculated.
The thinking behind it: if you're already 30% disabled, the VA treats you as 70% "whole." When a second 30% condition is added, that second rating applies to the 70% you have left, not to 100%. So the second 30% becomes 30% of 70, which is 21%. Add that back to your original 30% and your combined rating is 51%, not 60%.
For a visual walk-through from the VA itself, their media program (theSITREP) put together a short explanation of VA math:
Video hosted on YouTube. Clicking play loads YouTube's services.
The VA implements the combining rule with a specific formula captured in Table I of §4.25. The calculator on this site implements that table exactly, using integer math at every step. Here's the formula the table is built on:
combined = 100 − (100 − A) × (100 − B) ÷ 100
Each intermediate result rounds to the nearest whole number. Only the final combined rating rounds to the nearest 10, and values ending in 5 always round up. So a calculated 55% becomes a final rating of 60%.
The bilateral factor
Conditions affecting both legs, both arms, or all four extremities get a small bonus under §4.26. The VA combines those paired ratings first, then adds 10% of that combined value to the total.
For example: a 20% rating for your left knee and a 10% rating for your right knee combine to 28%. Ten percent of 28 is 2.8, rounded to 3. So the bilateral factor contributes an adjusted value of 31% for that pair, which then gets combined with your other conditions.
The rule in §4.26(d) says the bilateral factor should only be applied when it actually produces a higher combined rating. If the standard calculation gives you a better number, that's the one the VA uses. The calculator does this check automatically and shows you both results.
Compensation rates
Monthly payment amounts come from the official VA compensation tables. Rates change each December based on the annual cost-of-living adjustment (COLA) tied to Social Security benefits. The calculator includes both 2025 rates (effective December 1, 2024, 2.5% COLA) and 2026 rates (effective December 1, 2025, 2.8% COLA). Use the rate selector in the top navigation to switch between them.
VA disability compensation is tax-free at the federal and state level.
Privacy
My VA Calculator does not collect, store, or transmit any personal information from veterans using the tool.
When you upload a PDF or screenshot of your ratings, the file is parsed, condition names and ratings are extracted, and then the file is discarded. Your document is not retained. The parsed conditions appear in your browser and exist only in your browser session. When you close the tab, they're gone.
The calculator runs entirely in your browser. Your conditions, dependent information, and calculated rating never leave your device. There are no analytics, no tracking scripts, and no cookies used for advertising.
The About page includes one embedded video from YouTube (linked above). The video does not load or transmit any data to YouTube until you click the play button. If you do click play, YouTube's standard privacy policy and tracking applies to that interaction. The thumbnail image shown before you click is served by YouTube as part of their standard thumbnail system.
The feedback form on the calculator page is the other third-party service. If you submit feedback, your message (and your email address, if you choose to provide one) is sent through Formspree to the site owner. This is used only to respond to your message and improve the tool. Your feedback is not shared with anyone else.
This site is not affiliated with, endorsed by, or connected to the U.S. Department of Veterans Affairs. It is provided for informational purposes only. Always verify your rating at VA.gov.
Support this project
My VA Calculator is free and will stay free. No ads, no data collection, no paywalls. If it saved you time or gave you confidence in your rating, and you're in a position to give back, you can support future development here.
Appreciated but never expected.