How to use it
Use this educational projection to compare fixed-rate compounding scenarios, not to predict an investment.
- Enter principal, contribution, nominal annual rate, years, and compounds per year.
- Choose whether contributions occur at the start or end of each full compound period.
- Calculate the projected balance, total contributed, and estimated interest.
Worked example
- Input
10,000 principal · 100 monthly · 6% · 2 years · monthly
- Output
End-period projected balance: about 13,814.79
The exact display uses the selected locale and market currency.
Method and definitions
- Principal uses P(1+r/n)^(nt); periodic deposits use an ordinary-annuity or annuity-due geometric series.
- Only full contribution periods add deposits; principal still compounds through any fractional final period.
Limits and edge cases
- The model excludes fees, tax, inflation, rate changes, missed contributions, and market risk.
- The rate must exceed −100%, frequency is 1–365, and the term is limited to 100 years.
Privacy
All input and output stays in this tab. Rigula does not upload, store, or include it in a share URL.
Sources
