Follow invidion on Twitter

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.

Recent Financial Topics


The tech shares boom is a product of greed and frustration. Sure, people are tempted by gains. But investors are disgusted at the terrible returns in safe deposit accounts and are moving into riskier assets.

RUTH SUNDERLAND: Heading for tech trouble?
24/01/2021 06:01 PM

Kenny Wilson only joined from Cath Kidston in 2018 but will share in the windfall thanks to the boot-maker's £3.5billion valuation. The valuation would also hand £350m to 22 senior staff.

Dr. Martens boss to net estimated £58m from float
24/01/2021 06:01 PM

Rishi Sunak has proposed moving officials to the hub, with locations thought to include Leeds, Teesside and Newcastle. Mandarins have been accused of trying to engineer the selection of Newcastle.

Bitter battle breaks out over plans for Treasury North
24/01/2021 06:00 PM