Saving and personal budgets

Effective annual rate calculator

The effective rate includes interest on interest: (1 + nominal rate / periods)^periods − 1.

Your numbers

Use the units shown. Results update as you change valid inputs.

YOUR RESULT

The effective rate includes interest on interest: (1 + nominal rate / periods)^periods − 1.

THE NUMBERS, EXPLAINED

How to use this calculator.

The effective rate includes interest on interest: (1 + nominal rate / periods)^periods − 1.

Start with your inputs

Enter nominal annual rate (%), compounds per year. Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.

InputExample value
Nominal annual rate (%)12
Compounds per year12

A worked example

With the example inputs above, effective annual rate (%) is 12.682503. Change the inputs to explore your own scenario.

Putting the example numbers into the formula

Effective annual rate (%)
((1+(12) ÷ 100 ÷ (12))^(12)-1) × 100 = 12.682503

All results for the example inputs above
ResultExample answer
Effective annual rate (%)12.682503

How this is calculated

Effective annual rate (%)

((1+a ÷ 100 ÷ b)^b-1) × 100

Symbols and units
a
Nominal annual rate (%)
b
Compounds per year

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions and limits

The effective rate includes interest on interest: (1 + nominal rate / periods)^periods − 1.

Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.

Questions about this tool

What does the result tell me?

Effective annual rate (%). The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.

Why might another calculator differ?

Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: The effective rate includes interest on interest: (1 + nominal rate / periods)^periods − 1.

Are my inputs stored or sent to AI?

Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.

Further reading

Investor.gov: financial planning tools ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

Review status

Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.

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