Compound Interest Calculator
See how a starting balance and monthly contributions grow with compound interest — and how much of the total is growth versus what you put in.
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Adjust for Inflation
Show values in today's purchasing power
Your Custom Fields
No custom fields yet. Add your own expenses, income, or one-time costs to personalize your plan.
Your Enough Plan
Enough Number: $0
Projected: $85,526
Compound Growth
Yearly Breakdown
| Year | Balance | Contributed | Growth | Monthly |
|---|---|---|---|---|
| 0 | $0 | $0 | $0 | $500 |
| 1 | $6,190 | $6,000 | $190 | $500 |
| 2 | $12,814 | $12,000 | $814 | $500 |
| 3 | $19,901 | $18,000 | $1,901 | $500 |
| 4 | $27,484 | $24,000 | $3,484 | $500 |
| 5 | $35,598 | $30,000 | $5,598 | $500 |
| 6 | $44,280 | $36,000 | $8,280 | $500 |
| 7 | $53,570 | $42,000 | $11,570 | $500 |
| 8 | $63,510 | $48,000 | $15,510 | $500 |
| 9 | $74,146 | $54,000 | $20,146 | $500 |
| 10 | $85,526 | $60,000 | $25,526 | $500 |
Monthly Savings Target
$0
per month to reach your goal
Current: $500
You're on track with $500 surplus per month
What If?
+$100/mo
Add $100 per month
No change
$102,631
+$200/mo
Add $200 per month
No change
$119,736
-2% return
Bear market scenario
No change
$77,182
What If You Saved Your Next Raise?
| Scenario | Final Monthly | Total Saved (10yr) |
|---|---|---|
| Save Nothing | $500/mo | $85,526 |
| Save 50% | $640/mo | $94,512 |
| Save ALL | $814/mo | $104,693 |
Saving ALL your raises instead of nothing nets you $19,167 more over 10 years.
Life Seasons
Add upcoming life events to see how they affect your monthly budget.
Click an event above to add it to your timeline.
How You Compare
Key Insights
- At your current savings rate, you won't reach your enough number in the given timeline.
- At this rate, you'll hit your goal 10 years early.
- Over 10 years, compound interest can turn consistent small contributions into significant wealth.
- Your enough number of $0 was calculated from your advanced settings.
- Your savings rate is ~8% — every dollar counts. Can you find $50 more per month to boost it?
- Compound interest adds $25,526 (43%) on top of your contributions — time is your greatest asset.
Export Results
Your Enough Plan
Enough Number: $0
Projected: $85,526
Compound Growth
Yearly Breakdown
| Year | Balance | Contributed | Growth | Monthly |
|---|---|---|---|---|
| 0 | $0 | $0 | $0 | $500 |
| 1 | $6,190 | $6,000 | $190 | $500 |
| 2 | $12,814 | $12,000 | $814 | $500 |
| 3 | $19,901 | $18,000 | $1,901 | $500 |
| 4 | $27,484 | $24,000 | $3,484 | $500 |
| 5 | $35,598 | $30,000 | $5,598 | $500 |
| 6 | $44,280 | $36,000 | $8,280 | $500 |
| 7 | $53,570 | $42,000 | $11,570 | $500 |
| 8 | $63,510 | $48,000 | $15,510 | $500 |
| 9 | $74,146 | $54,000 | $20,146 | $500 |
| 10 | $85,526 | $60,000 | $25,526 | $500 |
Monthly Savings Target
$0
per month to reach your goal
Current: $500
You're on track with $500 surplus per month
What If?
+$100/mo
Add $100 per month
No change
$102,631
+$200/mo
Add $200 per month
No change
$119,736
-2% return
Bear market scenario
No change
$77,182
What If You Saved Your Next Raise?
| Scenario | Final Monthly | Total Saved (10yr) |
|---|---|---|
| Save Nothing | $500/mo | $85,526 |
| Save 50% | $640/mo | $94,512 |
| Save ALL | $814/mo | $104,693 |
Saving ALL your raises instead of nothing nets you $19,167 more over 10 years.
Life Seasons
Add upcoming life events to see how they affect your monthly budget.
Click an event above to add it to your timeline.
How You Compare
Key Insights
- At your current savings rate, you won't reach your enough number in the given timeline.
- At this rate, you'll hit your goal 10 years early.
- Over 10 years, compound interest can turn consistent small contributions into significant wealth.
- Your enough number of $0 was calculated from your advanced settings.
- Your savings rate is ~8% — every dollar counts. Can you find $50 more per month to boost it?
- Compound interest adds $25,526 (43%) on top of your contributions — time is your greatest asset.
Export Results
Enough Number
$0
Progress
0%
How Compound Interest Works
Compound interest is interest earned on both your original money and the interest it has already earned. Over time this snowballs: each period's growth becomes part of the base that grows next period. The longer the runway, the more dramatic the effect — which is why starting early beats starting big.
With monthly compounding, growth is applied twelve times a year rather than once, so your effective annual growth is slightly higher than the stated rate. Our calculator compounds monthly and lets you add a recurring monthly contribution on top of your starting balance.
A Simple Example
Invest $10,000 today and add $300 a month at a 7% annual return. After 30 years you'd have roughly $430,000 — of which about $118,000 is money you contributed and over $310,000 is compound growth. The growth eventually dwarfs the contributions; that crossover is the power of compounding.
What Changes the Outcome
Time is the biggest factor, followed by rate of return and contribution amount. Even a one-percentage-point difference in return compounds into a large gap over decades. Toggle inflation to see your future balance in today's purchasing power.