- Starts from your investable assets and assumes you begin withdrawing today.
- Each year it subtracts a spending amount plus your healthcare cost (both grossed up for taxes at the rate you pick) and adds Social Security once you claim it. What's left grows on a conservative floor: the model holds your first 8 years of spending in cash (a stress-test assumption, not a recommendation to hold that much cash), and the rest grows at 3% a year above inflation, the worst 30-year real return US stocks have delivered since 1871.
- Healthcare is funded alongside your spending, not out of it, which is why Confidence Spend is your living expenses. Before 65 the model uses the full price of a marketplace plan at your age, with no subsidy; from 65 it switches to Medicare, Medigap Plan G and typical out-of-pocket. Both come from the same 2026 cost table the app uses.
- Your Confidence Spend is the highest spending amount that still keeps you covered to age 90 at that conservative return.
This is a deliberately conservative floor on a single worst-case return path. The healthcare figure is a flat estimate: it assumes you get no help paying your premiums before 65 (if you expect a subsidy,
estimate your ACA subsidy and enter it above), and no Medicare surcharge for higher incomes (IRMAA) after 65. The full app goes further still: your real tax brackets instead of a flat rate, your actual premium help and Medicare surcharges year by year, and per-account modeling of every withdrawal.
See everything the app models →
Want the whole thing, including a worked example you can reproduce on this calculator line by line? Read the full Confidence Spend methodology →
