SSDI benefit amounts are calculated using a formula based on your earnings history, not on how severe your condition is or how much money you need. Understanding how the Social Security Administration arrives at your monthly payment involves learning about primary insurance amount, how work credits factor in, and what happens when you reach full retirement age. This section explains the mechanics behind the numbers.
These articles answer questions like: How does Social Security use my past earnings to set my benefit amount? What is the primary insurance amount and why does it matter? How do family members' benefits get calculated if I'm the wage earner? What happens to my payment if I work while receiving SSDI? How do cost-of-living adjustments affect what I receive each year?