How this retirement savings gap calculator works
Method: accumulate (monthly contributions compounded at your return rate + current balance growth), then demand = (monthly spending − Social Security) × 25 (the 4% rule inverted), grown with 2.6% CPI to your retirement year. The 'extra monthly' solves the shortfall through the remaining saving years — a concrete number, not a vague 'save more'. All assumptions are adjustable and clearly labeled; nothing you type leaves this page.
Frequently asked questions
How much do I actually need to retire?
The 4% rule framework: annual spending ÷ 0.04. Want $54,000/year after Social Security covers $26,400? You need a $690k portfolio. Inflation caveat: 4% is a 30-year safe withdrawal estimate; 3.5% is the cautious 2026 number.
What savings rate keeps me on track?
Rule of thumb (Fidelity): 1× salary by 30, 3× by 40, 6× by 50, 8× by 60 — but this calculator runs the actual compound math with your inputs instead of the table. A 15% rate from age 30 generally hits 8× with average returns.
Is Social Security going to be there?
SSA trustees project the trust fund depletes ~2086 after paying a reduced ~80% from 2034 under current law; the 2025 budget deal partially patched it near-term. Treat the calculator's SS input conservatively — many planners haircut it 20%.