Free financial tools
Find the month-end deposit needed to reach a future dollar target, then inspect the contribution path and the assumptions behind it.
02 / The result
Showing the editable example above. Modeled values, not a forecast.
Compare the required USD 360.42 monthly deposit with cash actually left after bills. If it does not fit, test a later target date or a smaller target before assuming a higher return. If the goal is quoted in today’s prices, estimate its future cost with the inflation calculator first.
Before interpreting the result
A nominal annual rate compounded monthly, a fixed future-dollar target and constant month-end deposits. The contribution is rounded up to the nearest cent. Taxes, fees and inflation are excluded; the assumed growth rate is not guaranteed.
Required deposit = max[0, (target − P × (1 + r)^n) / A], where A = [(1 + r)^n − 1] / r. At zero interest, A = n.
Background reading: Investor.gov: free financial planning tools. These references explain the concepts; they do not endorse this calculator.
03 / Visual evidence
Vertical scale: USD. Horizontal scale: Year. Lines join the calculated points; no probability is implied.
Shared value scale; zero is included. These are modeled scenarios using your assumptions, not observed market data. The table provides every plotted value.
USD amounts are displayed to two decimal places. Calculations use unrounded internal values. Scroll across a wide table on smaller screens.
| Year | Projected balance (USD) | Total contributed (USD) | Modeled interest (USD) |
|---|---|---|---|
| 0 | 5,000.00 | 5,000.00 | 0.00 |
| 1 | 9,608.93 | 9,325.04 | 283.89 |
| 2 | 14,405.63 | 13,650.08 | 755.55 |
| 3 | 19,397.76 | 17,975.12 | 1,422.64 |
| 4 | 24,593.27 | 22,300.16 | 2,293.11 |
| 5 | 30,000.46 | 26,625.20 | 3,375.26 |
Change one assumption at a time, then compare the result. A scenario is a way to examine a decision, not a promise of an outcome.
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