Project long-term wealth growth, compound interest accumulation, and the future value of your recurring savings.
The Investment Calculator helps you project how your savings will grow over time through compound interest. By entering an initial starting deposit, expected annual return, and optional monthly additions, you can see your projected portfolio balance years into the future.
All projections run locally in your browser. Your private investment plans and savings amounts are never stored or uploaded anywhere.
Individuals model expected nest egg values at retirement age based on steady monthly index fund contributions.
Parents calculate how monthly 529 plan contributions will grow over an 18-year horizon before college.
Savers project how high savings rates accelerate reaching their target financial independence milestone.
Input your initial investment or current portfolio value.
Add the amount you plan to save and invest each month.
Choose your estimated annual rate of return and number of investment years.
Visual breakdown separating total principal deposited from compound interest earned
Year-by-year projected portfolio growth table
Customizable compounding frequency (annual, semi-annual, monthly)
100% private in-browser computation with zero cloud storage
Starting with $5,000 and contributing $500 per month at 7% average annual return.
Compounding allows the earned interest to significantly surpass the total cash deposited over time.
Solution: Verify your compounding frequency and annual return rate. A conservative diversified index fund return is typically modeled at 6% to 8%.
MWT Labs tools are built using modern web primitives—including WebAssembly, Web Workers, and native HTML5 Canvas / Cryptography APIs. When you process images, parse PDF documents, format JSON payloads, or calculate financial schedules, execution happens strictly within your local browser memory sandbox.
Compound interest earns returns not only on your initial deposit (principal) but also on the accumulated interest from previous periods. Over long time horizons, this compounding effect accelerates your total portfolio growth exponentially.
A lump-sum investment starts compounding your entire balance from day one. Recurring monthly contributions allow you to build wealth steadily over time through dollar-cost averaging, even with a smaller starting amount.
The Rule of 72 is a quick mental math shortcut: Divide 72 by your expected annual interest rate to estimate how many years it will take for your investment to double in value (for example, at 8% interest, 72 / 8 = 9 years).
No. The calculator provides mathematical projections based on the constant annual rate of return you specify. Real-world financial markets experience volatility and fluctuating returns over time.
Yes. All portfolio calculations and interest growth charts are computed entirely within your browser. No financial numbers are recorded or sent to any server.