What is compound interest?
Compound interest means your earnings can generate their own earnings over time, which can accelerate growth.
Compound Interest Calculator
Project long-term growth with contributions and compounding
Estimate how an initial investment and recurring monthly deposits can grow over time using conservative, expected, and stronger return assumptions.
Initial balance and monthly contribution planning
Conservative, expected, and stronger scenario ranges
Year-by-year checkpoints for easier planning
Enter savings details
Start with your initial balance, monthly contribution, return estimate, and a reasonable scenario range.
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Yearly checkpoints
Review the balance range at key milestones to see how return assumptions can change the long-term outcome.
| Year | Conservative | Expected | Higher |
|---|---|---|---|
| 5 | $48,374 | $51,637 | $55,172 |
| 10 | $100,134 | $113,669 | $129,493 |
| 15 | $169,950 | $206,088 | $251,774 |
| 20 | $264,122 | $343,778 | $452,965 |
| 25 | $391,147 | $548,915 | $783,986 |
| 30 | $562,483 | $854,537 | $1,328,618 |
Time matters most
Starting earlier usually helps more than trying to catch up later with much larger contributions.
Scenario ranges help
Using a return range gives a better planning picture than relying on one exact rate assumption.
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Compound interest FAQ
Do monthly contributions really matter?
Yes. Monthly deposits can materially increase the ending balance because each deposit gets time to compound.
Why use a return range?
A return range helps you plan around uncertainty instead of relying on one exact growth assumption.
Does this guarantee future returns?
No. The calculator provides projections based on fixed assumptions, and actual investment returns can vary.