See how your savings grow over time. Enter a starting balance, how much you add regularly, the interest rate, and how many years you will save for. The calculator shows your projected final balance, the total you will have contributed, and how much of the balance is interest. It is a clear way to set a savings goal or see the power of regular deposits and compounding.
Figures are before Resident Withholding Tax (RWT) on interest.
Your balance grows in two ways: the money you add, and the interest that money earns. Interest compounds, which means each period you earn interest on your deposits and on the interest already added. Over a long period, compounding does a surprising amount of the work, and the interest can become a large share of your final balance.
Sione starts with $1,000 and adds $100 a month for 10 years at 4.5% per year.
He contributes $1,000 plus $12,000 in deposits, which is $13,000 of his own money. With interest, the balance grows to about $16,300. That means roughly $3,300 of the final balance is interest, earned simply by saving steadily.
If he saved for 20 years instead of 10, the balance would be about $40,900, with over $15,000 of it interest. Time is the biggest lever.
No. The result is before Resident Withholding Tax. Your after-tax balance will be slightly lower, so use a slightly lower rate for a conservative estimate.
Use the rate your account or term deposit pays. You can check current figures on our NZ Interest Rates reference page.
This calculator is for anyone projecting how their savings grow over time with regular deposits and interest.
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