Finance
Compound interest calculator
Explore savings growth with interest and regular contributions.
Enter your values, review the period and select Calculate. Calculations run in your browser; your financial data is neither sent nor saved. The page downloads software resources.
Educational estimates assume constant rates and exclude taxes, fees, inflation and insurance. They are not an offer or financial advice. Loans use a nominal annual rate divided by twelve; this is not the total cost of credit. The savings calculator converts an effective annual rate to the chosen frequency. Contributions occur every compounding period.
Amounts from 0 to 1,000,000,000, up to two decimal places. Rates from 0 to 100%, up to six decimal places. Use a decimal point or comma without thousands separators. Use the same currency for all amounts.
Ready to calculate
What this tool does
Estimate a final balance, contributions and interest under a constant rate, with a schedule by compounding period.
Variables and assumptions
Initial capital is the amount you already have; the contribution repeats every compounding period. A nominal annual rate is divided by frequency, while an effective annual rate is converted to an equivalent periodic rate. The term determines the number of periods.
How to interpret the result
Final capital combines contributions and estimated interest. Total contributions are not a return: subtract them from final capital to identify interest. Use the evolution table to compare beginning and end contributions with other assumptions held constant.
Educational estimate; not personalized financial advice or a commercial offer.
How to use it
- Enter initial capital and annual rate; choose effective or nominal.
- Choose years, frequency, contribution per period and beginning or end timing.
- Calculate and inspect the schedule; reset to compare assumptions.
Verifiable example
- Input
- Initial capital 1000, effective annual rate 10%, two years, no contributions.
- Expected result
- Final balance 1210; total contributed 1000; interest 210.
Limitations to review
- Excludes inflation, taxes and fees. A constant-rate simulation is not a guaranteed investment return.
- Nominal rates are divided by frequency; effective rates use equivalent periodic rates. Contributions occur each period, not necessarily monthly.
Related tools
Browse all guides. Local processing: the page downloads HTTP resources but does not send files or input data to a server for these functions.