Effective Interest Rate Calculator

Calculate the effective interest rate (EIR) and effective annual rate (EAR) for accurate loan cost comparison.

Free • Accurate • Instant Results

Effective Interest Rate Inputs

Nominal (Stated) Rate

Compounding Periods/Year

Principal (for illustration)

Effective Rate

📊

8.30%

Nominal Rate

📈

8.00%

Difference

➕

0.30%

Annual Cost

💰

$830

🤖

AI Insights

Personalized analysis based on your inputs

💡

True Borrowing Cost

Your nominal 8% rate compounds to an effective 8.30% — always compare effective rates when shopping for loans or accounts.

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Formula Used

Effective Interest Rate

EIR = (1 + nominal/n)^n − 1

Variables

n= Compounding periods per year

Example

8% nominal compounded monthly: EIR = (1+0.08/12)^12 − 1 = 8.30%

Frequently Asked Questions

More frequent compounding means interest is calculated and added more often, so the true (effective) cost or yield is higher than the stated nominal rate.

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Disclaimer: This calculator is for informational and educational purposes only. Results are estimates based on inputs you provide. They are not financial, tax, investment, or legal advice. Consult a qualified financial professional before making financial decisions. Actual results may vary based on market conditions, tax laws, and individual circumstances.