Current Plan vs Saved Plan
Balance over time
Year by year
| Year | Contributed | Total contributed | Growth | Balance |
|---|
Where To Go Next
If you want to connect this growth with how much of your income you actually invest, open the Savings Rate Calculator. If you want to turn this growth into a full financial independence plan, open the FIRE Calculator. If you want to test whether your current portfolio could reach financial independence by retirement age, try the Coast FIRE Calculator. If you want to compare how much waiting can cost, try the Started Investing Earlier Calculator. If you want a real broad-market return snapshot to compare against your assumptions, open the Global Index Fund Return Tracker. If you only want to estimate the portfolio size your spending requires, the 4% Rule Calculator is the quickest next step.
How To Use The Calculator
Use this calculator when you want to understand the mechanics of compounding without mixing in retirement assumptions too early.
- Enter the balance already invested today.
- Add a monthly contribution you could realistically keep making.
- Use a conservative long-run return, not the hottest recent market period.
- Set the time horizon and compare at least two or three cases.
- Review the chart and table to see when growth starts doing more work than contributions.
Method And Assumptions
The calculator projects a starting balance forward, adds monthly contributions, and compounds growth using the annual return you enter. It is a clean planning model, which is why it is useful.
It also means the model leaves out taxes, fees, changing contributions, inflation, and year-by-year volatility. Real portfolios are bumpier than the output line here, even if the long-run average return ends up similar.
This is not financial advice. It is a way to understand the shape of a plan before you attach bigger decisions to it.
Real Example
Imagine an investor starts with 100,000, adds 5,000 per month, and assumes a 5% real annual return for 20 years. The final value is driven by three forces: the original balance, total contributions, and growth earned on both.
If lowering the return to 3.5% makes the final value much smaller, that does not mean the plan is bad. It means the plan relies on market returns, and the investor should understand that risk before using the number in a retirement projection.
How To Interpret Results
The final value is not a forecast. It is the answer to the scenario you entered.
The useful read is how the pieces shift over time. If most of the final value still comes from contributions, pace matters most. If growth dominates later, staying invested for long enough is doing the heavy lifting.
Compare a base case, a lower-return case, and a shorter-horizon case. That is far more honest than one optimistic projection.
Common Mistakes And Limitations
Common mistakes include using a recent strong return as the long-run assumption, forgetting inflation, or assuming contributions will stay perfectly steady for decades.
Run lower-return cases and shorter horizons to see how fragile the result is. The calculator cannot tell you which asset to buy or whether the return you entered matches your real portfolio risk.
FAQ
Should I use real or nominal returns?
Either can work, but be consistent. A real return keeps results closer to today's purchasing power.
Does this include taxes?
No. Tax treatment depends on account type and country.
Why does time matter so much?
More time gives earlier contributions more years to earn returns on prior returns.
Can this predict my actual portfolio?
No. It is a scenario model. Real markets will move unevenly.