How it works
This tool focuses on a constant monthly contribution. It grows the current balance first, then calculates the monthly deposits that fill the remaining target under the entered nominal return assumption.
The formula
Keep currency, units and time periods consistent. Percentage inputs use percentage points (enter 5 for 5%). Results are rounded only for display; tiny nonzero values may use scientific notation. Undefined ratios are shown as unavailable.
A $250,000 target, $25,000 current balance, 15 years and 6.5% nominal annual return require $605.82 per month at month-end. Full-precision new deposits total $109,048.48; modeled growth is $115,951.52.
Calculation method
Starting earlier adds both contribution periods and compounding time. Beginning-of-month contributions receive an extra month of growth. A zero return assumption produces a plain savings calculation without dividing by a zero rate.
Interpretation
An optional contribution increase is shown separately from the level-payment answer. It solves for a starting monthly amount, then increases that amount after each completed year. It does not silently replace the simple monthly plan.
Limitations
Budget comparisons hold the entered monthly budget constant. They show its projected value and the target gap under the same return and timing assumptions. The results are scenarios and do not guarantee that a goal will be funded.
Method and reference sources
Method and content checked 2026-09-20. These sources provide background, not endorsement or professional certification. The formula and limitations above define this calculator.
- Investor.gov — Savings Goal CalculatorSavings targets, starting balances and regular contributions under an assumed return.
- Investor.gov — Understanding FeesInvestment fee and compounding context; enter the terms of your fund or account.
Frequently asked questions
Does an affordable monthly contribution guarantee the target?
No. The contribution solves a model using the return and time you enter. Investment returns are uncertain, and fees or taxes outside the model can reduce the outcome.
What is a worked example for Required Monthly Investment?
A $250,000 target, $25,000 current balance, 15 years and 6.5% nominal annual return require $605.82 per month at month-end. Full-precision new deposits total $109,048.48; modeled growth is $115,951.52.