# How many days to interest compound goal

I usually use this google sheets formula to calculate the compound interest, for 30 days. B2*((1+B3/100)^30)
B2=invested amount
B3=daily percentage

I would like to have a formula to calculate how many days I would have to wait to gain a specific amount.

I would fill : invested amount, daily percentage, and goal amount and the formula will calculate how many days is needed to achieve this.

Is it possible to have this?

Hope I explained it well, english is not my natural language

For the sake of clarity, let's assume that in addition to entering the present value (i.e., "invested amount") in B2 and the daily interest in B3, you will also enter into B4 the target future value.

This formula should tell you how many days it will take to reach that target future value:

=ROUND(NPER(B3,0,-1*B2,B4))

NPER is the "Number of PERiods" function.

The second parameter (currently set to 0) is the amount of any additional regular payments you will make into the investment per period (in your case per day, which is zero).

The present value must be multiplied by -1 in the formula, because as far as accounting goes, you are paying that amount up front, not earning/gaining it.

ROUND is used simply to eliminate partial periods, which, being days, are irrelevant.