How to use this tool
Choose whether to solve for the monthly contribution or the time to reach your goal.
Enter the starting balance, goal and assumed effective annual return. The result is a constant-return scenario before tax and fees.
Goal = P(1+r)^n + C[(1+r)^n−1]/r
Worked example
$232.69 · monthly contribution
Fixed example using the settings below. Monetary examples use USD; dates and times use their stated reference values. This example stays unchanged when you edit your calculation.
Example inputs
- Starting balance: 1000
- Savings goal: 10000
- Effective annual return (%): 4
- Target months: 36
- Monthly contribution: 200
- Solve for: Monthly contribution
Method illustration: With no growth, 1,000 toward a 10,000 goal over 36 months needs 250 per month.
Assumptions and limits
- Assumed rates remain constant. Values are estimates before tax and fees unless entered explicitly. No return or affordability is guaranteed.
- Calculations use full precision; displayed money is rounded to cents.
Method reference: Investor.gov saving and investing tools
Check or report a result
Check the units, selected calculation and assumptions first. Compare the fixed example above with your inputs to identify what changed.
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