THE NUMORIX GUIDE
How to use the Social Security Calculator
Last reviewed September 14, 2026
What this calculator does
Ideal-age mode generates ages 62 through 70 from a hardcoded $2,800 full-retirement-age benefit.
Formula and method
Ideal-age mode generates ages 62 through 70 from a hardcoded $2,800 full-retirement-age benefit. It applies a 30% reduction at age 62, a 0.556% per-year reduction through age 67, and an 8% per-year delayed credit through age 70, then multiplies the monthly benefit by 12 and years from claiming age to entered life expectancy. Compare-two mode uses the two entered monthly benefits and the same lifetime-months calculation.
Variables and inputs
Ideal-age mode displays the engine's fixed FRA benefit and asks for life expectancy. Compare-two mode asks for two claim ages, two monthly benefits, and life expectancy. Birth year, investment return, and COLA exist in the input type but are not used in the current calculation.
Worked example
With life expectancy 82, the ideal-age row at 62 is $2,800 x 0.70 = $1,960 per month and has 20 years of payments, so its simple lifetime total is 1,960 x 12 x 20 = $470,400. The age-70 row is $2,800 x 1.24 = $3,472 per month for 12 years, or $3,472 x 12 x 12 = $499,968.
How to interpret the result
The highest lifetime total is determined by the entered life expectancy and the route's assumed benefit curve. It does not identify a universally ideal claiming age. Work history, actual earnings record, taxes, spouse and survivor benefits, health, and the official benefit estimate can change the decision.
Common mistakes to avoid
Do not treat the $2,800 figure as a personal benefit quote. In compare mode, enter the actual monthly benefits for the two options being compared. Do not assume the unused birth-year or COLA fields adjust the current result.
Assumptions and limitations
The benefit curve is an approximate hardcoded 2024-style illustration and is not tied to the claimant's earnings record or current SSA formula. The model ignores taxes, earnings tests, spouse and survivor benefits, disability, cost-of-living changes, and investment of early payments.