Savings Goal Calculator
Find the monthly contribution needed to hit a savings goal, given a starting balance, time horizon, and expected return.
Inputs
5-7% is reasonable for diversified portfolios.
Required monthly contribution
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Total contributed (start + monthlies)
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Interest earned
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Gap above starting growth
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About Savings Goal Calculator
Math behind it
The future-value formula for an annuity: FV = PMT × ((1+i)n − 1) ÷ i. Solving for PMT gives the monthly contribution needed to bridge the gap between your starting balance’s growth and the goal.
Picking an expected return
For long-term US stocks, ~7% real (10% nominal − 3% inflation) is a common assumption. Diversified mixes: 5-7%. Cash-equivalent goals: 1-3%. Conservatism matters — overestimating return underestimates the contribution needed.
What if I can’t afford the monthly?
Three levers: increase the time horizon, lower the goal, or accept more risk (and a higher expected return). Stretching the horizon is usually the lowest-risk choice.