Financial
Interest Calculator
Grow a principal with periodic compounding and optional monthly contributions.
Inputs
Interest Calculator
Result
Final balance
$16,470.09
- Total contributions
- $10,000.00
- Interest earned
- $6,470.09
- Effective annual yield
- 5.12%
How it's calculated
FV = P(1+r/n)^(nt) + PMT · ((1+r/12)^months − 1)/(r/12)
Common questions
What's the difference between simple and compound interest?
Simple interest applies only to the original principal. Compound interest earns interest on prior interest — the more frequent the compounding, the higher the effective yield.
Does compounding frequency matter much?
For typical rates the jump from monthly to daily is small (a few basis points). Rate and time matter far more.
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