Calculating your effective annual rate is straightforward once you know the Effective Annual Rate (EAR) formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the Effective Annual Rate (EAR) Calculator.
What is Effective Annual Rate (EAR)?
The Effective Annual Rate (EAR) calculation tells you your effective annual rate from a few simple inputs. The figure you are solving for here is the effective annual rate, expressed in percent.
The Effective Annual Rate (EAR) formula
The core formula is:
Effective annual rate = ((1 + Nominal annual rate ÷ 100 ÷ Compounding periods per year)^(Compounding periods per year) - 1) × 100Here is what each input means:
- Nominal annual rate — a percentage, such as an annual rate. Example: 12%.
- Compounding periods per year — a number. Example: 12.
How to calculate it step by step
- Write down the nominal annual rate (for example, 12%).
- Write down the compounding periods per year (for example, 12).
- Apply the formula above to get your effective annual rate.
- Double-check the result with the Effective Annual Rate (EAR) Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Nominal annual rate | 12% |
| Compounding periods per year | 12 |
| Effective annual rate | 12.6825% |
With nominal annual rate of 12% and compounding periods per year of 12, the effective annual rate works out to 12.6825%.
Example 2
With nominal annual rate of 24% and compounding periods per year of 12, the effective annual rate works out to 26.8242%.
| Result | Value |
|---|---|
| Effective annual rate | 26.8242% |
Example 3
With nominal annual rate of 6% and compounding periods per year of 12, the effective annual rate works out to 6.1678%.
| Result | Value |
|---|---|
| Effective annual rate | 6.1678% |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
- Annual rates must be converted to the period you are calculating for (for example, divide an annual rate by 12 for a monthly figure).
Prefer not to do the maths by hand? — the Effective Annual Rate (EAR) Calculator does it instantly, for free, with the formula and a worked example built in.
Related calculators
Continue exploring finance calculators with these tools: SIP Calculator, EMI Calculator, CAGR Calculator, FD Calculator, RD Calculator.