What is Portfolio Compound Simulator?
The Portfolio Compound Simulator lets you model the long-term compound growth of your actual multi-stock portfolio. Unlike a simple compound calculator that handles one asset, this tool lets you define a complete portfolio with multiple US stocks and ETFs — each with its own allocation weight and expected annual return — and calculates the combined compound growth over time.
If you hold a mix of high-growth individual stocks like TSLA or NVDA alongside stable ETFs like SPY or SCHD, this simulator gives you a much more accurate projection than any single-asset calculator. You can see exactly how your current allocation will perform over 10, 20, or 30 years — and experiment with different weights to find the configuration you are most comfortable holding long-term.
The output shows your projected portfolio value year by year, along with total contributions versus total compound gains, making it easy to see how much of your future wealth will come from your own savings versus the markets working for you.
Why Use This Tool?
Most portfolio calculators either work with a single asset or use a fixed blended return that loses all nuance. If you hold TSLA at 20%, AAPL at 30%, and SPY at 50%, those three assets have very different expected return profiles — and simply averaging them into one number misses the compounding dynamics of each component.
The Portfolio Compound Simulator preserves the individual return rates of each asset while calculating the weighted compound growth of the whole portfolio. This means you can see the real impact of allocation decisions: what happens if you increase NVDA from 15% to 25%? What if you shift from individual stocks toward SPY? The answers are immediately visible in the projection chart.
How to simulate your portfolio compound growth
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1
Open the Portfolio Compound Simulator
Click Open Tool to access the simulator in your browser. No login or download needed.
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2
Add your first stock or ETF
Enter the ticker symbol of your first holding (TSLA, AAPL, SPY, QQQ, NVDA) and set its allocation percentage.
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3
Set the expected annual return per asset
For each asset, enter your expected annual return. S&P 500 historical average is approximately 10%, Nasdaq-100 approximately 14%, large-cap growth stocks vary widely. Use conservative estimates for realistic projections.
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4
Add all remaining holdings
Repeat for each position in your portfolio. Allocation percentages must sum to 100%. The simulator supports as many assets as your actual portfolio holds.
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5
Enter your portfolio value and time horizon
Input your current total portfolio value and the number of years for the projection (1-30 years).
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6
Run the simulation and read results
Click Calculate. The simulator displays year-by-year projected portfolio value in chart and table form, plus total contributions vs. total compound gains breakdown.
Frequently Asked Questions
How is this different from the DCA simulator?
The Portfolio Compound Simulator models compound growth on your existing portfolio value with custom per-asset allocations. The DCA Simulator models ongoing monthly contributions. Use the Portfolio Simulator for an existing lump-sum portfolio; use the DCA Simulator to model regular monthly investing.
How many assets can I add to the portfolio?
You can add as many assets as your actual portfolio holds. The simulator handles real-world multi-stock portfolios with 5 to 20+ positions.
What expected return should I set for stocks like TSLA or NVDA?
Historical returns for individual growth stocks vary significantly. Use a range of scenarios — conservative (10%), base (15%), and optimistic (20%) — rather than assuming recent exceptional returns continue indefinitely.
Does the simulator account for rebalancing?
The simulator assumes a static allocation compounding over time without periodic rebalancing. It is most useful for understanding directional outcomes rather than precise predictions. Annual rebalancing in practice would slightly smooth returns.
Can I include dividend-paying stocks?
Yes. Include the expected dividend yield in each asset's total annual return rate. For example, if a stock grows 8% per year and pays a 2% dividend yield you reinvest, enter 10% as the total expected return.
What if I want to add monthly contributions?
If you want to model both an existing portfolio AND ongoing monthly contributions, use the DCA Simulator alongside this tool, then combine the results. You can run both tools separately for different scenario planning.
What is a realistic long-term return for a diversified US stock portfolio?
A diversified US portfolio tracking the S&P 500 has historically returned about 10% per year (nominal) over 30-year periods. A Nasdaq-100-heavy portfolio has averaged around 14% with significantly higher volatility.
Is this portfolio simulator free?
Yes, completely free with no registration, no email, and no subscription required.
Try Portfolio Compound Simulator Now
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