Online calculator — enter the values and get the result instantly, with the formula and a worked example.
annuity = fixed regular amount of money
FV = future value
i = interest rate
n = number of periods
The sinking fund factor is a finance multiplier that tells you what fixed amount you must set aside each period to accumulate a specific target sum by a future date. In plain words, it answers the reverse of ordinary saving: instead of asking how much you will have, it asks how much you must regularly deposit to reach a goal you already know. Its value shrinks as the interest rate rises or the number of periods grows, because compounding does part of the work for you and each contribution can be smaller. That is its defining property: the longer your horizon and the higher the return, the lighter each individual payment needs to be. In everyday life it powers goal-based saving, such as building an emergency fund, saving for a car, a wedding, or a child's education. Businesses lean on it to set aside cash for replacing equipment or repaying a bond at maturity, which is exactly why it is called a sinking fund. Pension and insurance planning use the same logic to fund a promised future payout. Understanding it turns a vague intention to save into a concrete, disciplined monthly or yearly figure.
Required annual deposit
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Drag along the graph — amount saved in the given year (grows to the goal)
A company needs to save 90,000 Euros in 5 years for new equipment. The bank offers a 4% interest rate if we regularly deposit the same amount each year. How many Euros do we need to deposit at least to obtain these funds?
So we substitute into the formula above
annuity=90,000 * ((0.04/(1+0.04) to the power of 5)-1)
annuity= 90,000 * ((0.04/(1.04) to the power of 5 -1)
annuity=16616.44 Euros