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APR to APY Calculator

Convert nominal annual rates and effective annual yields using an explicit compounding frequency.

Your numbers

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Effective annual yield (APY)
12.6825%

Calculated from your inputs · rounded for display

Compounds per year12

Rate conversion only; assumes constant rates and no fees, taxes or cash withdrawals.

Your calculation, step by step

No black boxes
  1. APY = (1 + APR/k)^k − 1.

What if things were different?

Save up to three scenarios, then change your inputs to compare the possibilities.

How to use this calculator

  1. Enter your own values in the labeled fields. Check the units and assumptions before comparing results. Only the fields needed for your selected calculation mode are shown.
  2. Your answer updates automatically. Review the calculation steps to see exactly how it was calculated.
  3. Copy, share, save, or download your result. Saved inputs stay on this device.

How the calculation works

APY = (1 + APR/k)^k − 1; APR = k[(1+APY)^(1/k) − 1]

APR here is a nominal rate before fees. APY includes within-year compounding. The conversion assumes a constant rate, fixed compounding frequency and no deposits or withdrawals during the modeled year. Review the units, period and assumptions before comparing scenarios. Displayed values are rounded, while the underlying calculation retains its available precision.

A worked example

12% nominal interest compounded monthly gives (1 + 0.12/12)^12 − 1 = 12.6825% APY.

Reading your result

Use the main result together with its units and supporting figures. Display values are rounded; calculations keep their underlying precision. A change in inputs or assumptions can change the answer. Compare the step-by-step working with your intended use before relying on an estimate.

Frequently asked questions

What assumptions does this calculation use?

APR here is a nominal rate before fees. APY includes within-year compounding. The conversion assumes a constant rate, fixed compounding frequency and no deposits or withdrawals during the modeled year.

Can I save or check a scenario?

The result includes the working and supporting values. Save and Restore keep inputs on this device; Copy, Download and Print export the result. Sharing a scenario explicitly includes the inputs in its link.

Sources & methodology

This calculator uses the mathematical identity and assumptions stated above. No current rates, prices, or external data are loaded. Conversion tools use international unit definitions.

Formula review: October 24, 2026. Read our methodology.