Result
Required monthly contribution
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This calculation is for informational purposes only and does not replace advice from a qualified professional. Formulas and rates may not fit your exact situation — double-check the figures before making decisions.
How it is calculated
This is the reverse of the future value of a deposit with contributions: there, a known contribution gives the final amount; here, a known target amount gives the required contribution. Formula: contribution = (target amount − starting capital × (1 + monthly rate)^term) ÷ (((1 + monthly rate)^term − 1) ÷ monthly rate).
The starting capital also grows from returns over the saving period — so the larger the starting amount and the higher the rate, the smaller the monthly contribution needed for the same goal. At zero starting capital and a zero rate, the calculation reduces to simply dividing the goal by the number of months.
If the computed contribution comes out negative, it means the starting capital alone, with no further contributions, will already grow to the goal ahead of schedule purely from returns — no extra saving is needed.