Calculator Form
Enter values below to estimate gross AER, net AER, real AER, equivalent periodic rates, and maturity values.
Example Data Table
| Opening Principal | Nominal Rate | Compounds/Year | Years | Contribution | Contribution Frequency | Gross AER |
|---|---|---|---|---|---|---|
| $10,000.00 | 6.25% | 12 | 5 | $200.00 | 12 | 6.4314% |
| $25,000.00 | 4.80% | 4 | 3 | $500.00 | 4 | 4.8863% |
| $5,000.00 | 7.10% | 365 | 10 | $100.00 | 12 | 7.3594% |
These sample rows help you test the calculator and compare how compounding frequency changes the annual equivalent rate.
Formula Used
1) Gross Annual Equivalent Rate
AER = (1 + r / n)n - 1
Where r is the nominal annual rate as a decimal, and n is the number of compounding periods each year.
2) Equivalent Periodic Rate
Periodic Rate = (1 + AER)(1 / m) - 1
Here m is your chosen target periods per year, such as 12 for monthly or 52 for weekly.
3) Equivalent Nominal Annual Rate
Equivalent Nominal = Periodic Rate × m
This converts the equivalent periodic rate into a quoted annual rate using the target frequency.
4) Net AER After Tax
Net AER = (1 + (r / n) × (1 - tax))n - 1
This estimates the effective annual return when tax reduces interest before reinvestment.
5) Real AER After Inflation
Real AER = ((1 + Net AER) / (1 + inflation)) - 1
This shows how much purchasing power grows after accounting for inflation.
6) Balance Growth
The page simulates growth over time using the effective annual rate, then adds recurring contributions at the selected deposit frequency.
How to Use This Calculator
- Enter your opening principal.
- Type the quoted nominal annual rate from your product.
- Enter how many times interest compounds each year.
- Set the total investment term in years.
- Add any recurring contribution amount.
- Enter the contribution frequency per year.
- Choose the target periods for the equivalent rate conversion.
- Enter tax and inflation assumptions.
- Press Calculate Equivalent Rate.
- Review the results, chart, summary table, and export options.
Frequently Asked Questions
1) What does AER mean?
AER means Annual Equivalent Rate. It converts a quoted rate with compounding into one comparable yearly rate. That helps you compare savings products fairly, even when they compound at different intervals.
2) Why is AER usually higher than the nominal rate?
AER includes compounding. When interest is added during the year, later periods earn interest on earlier interest. That extra growth makes AER equal to or higher than the quoted nominal rate.
3) Does more frequent compounding always increase AER?
Yes, when the nominal rate stays the same, more frequent compounding raises the effective annual result. The improvement becomes smaller as frequency gets very high, but it still moves upward.
4) What is an equivalent periodic rate?
It is the rate for another payment or reporting interval that produces the same annual effect. For example, you can convert an annual equivalent result into an equivalent monthly or weekly rate.
5) Why include tax in the calculator?
Tax can reduce reinvested interest and lower your effective return. Showing net AER gives a more realistic estimate of what your money may actually earn after deductions.
6) Why show a real AER after inflation?
Inflation reduces purchasing power. Real AER helps you judge whether an investment is truly growing in value, not just increasing in nominal dollars.
7) Can I use this for recurring deposits?
Yes. Enter the extra contribution amount and its yearly frequency. The calculator then estimates how those recurring additions change maturity value, earnings, and the growth chart.
8) Is this calculator useful for comparing loans too?
It helps compare rate structures, but borrowing costs also depend on fees, payment timing, and amortization rules. For loans, use AER alongside full repayment and fee analysis.