Decision instrument
Compound Interest Calculator
Use the Compound Interest Calculator in your browser.
Your inputs
Adjust the fields and review the result in this workbench.
Interpretation
How Compound Interest works
The calculator combines compound growth on the starting balance with contributions made at the end of each whole month. It converts the selected annual, quarterly, monthly, or daily compounding convention into an equivalent monthly rate before valuing those monthly contributions.
Example
Key features
A realistic example to show how this tool can support an actual decision.
Formula
A = P(1 + i)^m + PMT × [((1 + i)^m − 1) / i], where i is the equivalent monthly rate and m is the number of months.
- Compound growth on an initial balance
- Monthly contributions with an explicit month-end assumption
- Annual, quarterly, monthly, or daily nominal compounding
- A separate view of total contributions and estimated growth
Avoid mistakes
Common mistakes
A few things that can lead to misleading results or poor decisions.
Related tools
Keep exploring
Continue with closely related tools in the same decision path.