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Interest Rate and Compound Interest Calculator / Solver.


Click here to launch the calculator

Use this calculator to work out Annual Percentage Rates, or perform calculations relating to loans and interest rates.

(Requires Flash Player 7 or higher).
You can use this calculator / solver to:
1. Work out the Annual Percentage Rate (APR) from a monthly rate of interest, or vice versa. (You can use change the interest period from monthly to daily, weekly, quarterly or half-yearly).
2. Work out the factors in Compound Interest Loan calculations, based upon three of the known factors. Therefore, you need to enter three of the following values:
  • Initial Value (i.e. the amount of money that is borrowed)
  • Interest Rate
  • The duration / length of the loan (in years)
  • The total amount of money that is repaid (i.e. initial value + interest)
Points to be aware of:
All results are rounded down to 4 decimal places, and this should be sufficient for most purposes. You can round this down further yourself (i.e. to 2 decimal places).
When enter 'part years' in the loan calculator (i.e. 7 years and 10 months), these need to be added as a fraction.
i.e. To work out 10 months as a decimal fraction, divide 10 by 12, and this gives the result 0.8 - therefore, enter 7.8 into the calculator. Any results calculated this way will also show the years and months underneath.
The figures projected by the calculator are only for guidance purposes - whilst we aim to ensure the accuracy of our calculators, we can take no responsibility for the usage made of the calculations generated on this site.

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