Investment Calculator: Plan Your Financial Future with Precision
Use this Investment Calculator to see how your money could grow when you combine a lump-sum with monthly deposits. Enter four numbers—starting amount, monthly contribution, years, and annual rate—and the tool instantly applies monthly compounding. Compound interest generates roughly 80 % of long-term equity gains (JP Morgan Guide to the Markets, 2023). Adjust any field to test new scenarios and keep your financial plan on track.
Investment Calculator
Investment Result
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How to use the tool
Initial investment – type your opening lump-sum. Example A: $20 000; Example B: $5 500.
Monthly contribution – add the amount you will deposit every month. Example A: $300; Example B: $850.
Investment period (years) – set the time horizon. Example A: 18 years; Example B: 25 years.
Annual interest rate % – enter the expected average return. Example A: 6.8 %; Example B: 8.2 %.
Press “Calculate” – the future value appears instantly and updates whenever you change any field.
Formula used
The calculator combines a single deposit (P) and equal monthly deposits (PMT) with monthly compounding:
The tool projects the future value of combined lump-sum and monthly deposits using monthly compounding (Investopedia, “Future Value”).
How does compound interest work?
Interest is added to principal each period, and new interest accrues on that larger balance (Federal Reserve Education, 2023).
How accurate are the results?
The math is exact, yet real returns vary with fees, taxes, and market changes (SEC Investor Bulletin, 2022).
What rate should I enter?
Use historical averages for your asset class; U.S. large-cap stocks averaged 10 % annually (Morningstar Market Report, 2023).
Can I factor in inflation?
Subtract expected inflation—currently 3.2 %—from your nominal rate to get a real return (BLS CPI Summary, 2024).
How often should I revisit my plan?
Review inputs at least yearly or after major life events (CFP Board Planning Guide, 2023).
What is the Rule of 72?
Divide 72 by your annual rate to estimate years needed to double your money (FINRA, 2022).
Does duration or contribution matter more?
Time amplifies compounding; extending by ten years can outweigh a modest deposit increase (JP Morgan Asset Management, 2023).
Important Disclaimer
The calculations, results, and content provided by our tools are not guaranteed to be accurate, complete, or reliable. Users are responsible for verifying and interpreting the results. Our content and tools may contain errors, biases, or inconsistencies. We reserve the right to save inputs and outputs from our tools for the purposes of error debugging, bias identification, and performance improvement. External companies providing AI models used in our tools may also save and process data in accordance with their own policies. By using our tools, you consent to this data collection and processing. We reserve the right to limit the usage of our tools based on current usability factors. By using our tools, you acknowledge that you have read, understood, and agreed to this disclaimer. You accept the inherent risks and limitations associated with the use of our tools and services.
