# How do you calculate interest?

the amount times % divided by 365= 1 day then multiply that by # of days for month etc... eg: 10000*4%/365=1.096/day 1.096*30=32.88 interest for 1 month

### How does one use a savings interest rate calculator?

One must first know a beginning balance. Then, an interest rate is required to calculate how much interest will be earned overall. Finally, one must also have a specified length of time during which money will be saved to earn interest. By plugging each of these factors into a savings interest rate calculator, one can calculate how much savings interest will be earned.

### How do you calculate effective interest rate when you do not know the rate of interest?

That depends on what you DO know. You might consider asking again, being more specific about what information you have. For example, if you know the amount of interest, the principal, and the length of time, you can readily calculate the effective interest rate even if you don't know the nominal value or how often it's compounded.