Compound Interest Calculator
Project investment growth with compound interest and optional contributions.
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Inputs
Updates live as you type — Calculate syncs a shareable URL.
Future value
$300,851
- Total contributions$130,000
- Interest earned$170,851
Breakdown
- Contributions
- Interest
Growth over time
BalanceContributions
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How this calculator works
Project investment growth with compound interest and optional contributions.
How is it calculated?
Monthly compounding: each month balance grows by (1+r), then the contribution is added.
Example
$10,000 start + $500/mo at 7% for 20 years ≈ $328k future value (illustrative).
Frequently asked questions
Is 7% guaranteed?+
No. Returns are hypothetical. Markets vary and fees/taxes are not modeled.