Term Deposit Calculator

How this calculator works

Frequently asked questions

How is the maturity value calculated?

In the compounding modes the calculator applies the standard formula: the amount times (1 + r/m) raised to the power of m times t, where r is the annual rate, m the number of crediting periods per year (12 monthly, 4 quarterly, 1 annual), and t the term in years. In the at-maturity mode it uses simple interest instead: the amount times r times t, paid in one sum at the end and never compounded. Tax is then charged on the gross interest, and any account duty on the year-end balances, giving the net maturity value.

What difference does the crediting frequency make?

At the same advertised rate, more frequent crediting pays slightly more, because each credited amount starts earning interest itself. At 3% on 10,000 over one year, monthly crediting yields 10,304.16, quarterly 10,303.39, annual 10,300.00, and simple interest the same 10,300.00. The differences are small at typical deposit rates but grow with the rate and the term, which is why two offers with the same headline rate can pay different amounts. The net annual yield readout makes them comparable.

Why can the real return be negative when the bank pays interest?

Because inflation erodes the value of the payout while it grows. If a deposit yields 2.2% after tax and inflation runs at 4%, the payout buys less at maturity than the deposited amount buys today, even though the balance went up. This is the difference between the nominal return, measured in money, and the real return, measured in purchasing power, and it has been the norm for cash-like savings over long stretches of history: across the last century, deposits and bills have delivered real returns of roughly 0 to 1% per year. The calculator shows the real value explicitly and warns when it falls below the deposit.

What tax rate and account duty should I enter?

The rate your own country applies to interest income, which this calculator never assumes for you. Some countries withhold a flat rate on interest (Italy takes 26%, for example), others tax it as ordinary income at your marginal rate, and a few exempt retail deposit interest entirely. The account duty covers the separate case of a recurring levy on the balance itself, such as Italy's 0.20% annual stamp duty; most countries have none, so it defaults to zero. Check both with your bank or tax authority and enter the values that apply to you.

Why is the real value hidden in the at-maturity mode?

Because in that mode the timing of the interest is ambiguous. Products quoted as simple interest sometimes pay the interest out during the term, for example yearly to a linked account, rather than in one sum at maturity. Adjusting a payout for inflation requires knowing when it happens: money received earlier loses less purchasing power than money received at the end. Rather than deflate every payment as if it arrived at maturity, which would overstate the loss for products that pay out early, the calculator shows the real value only in the compounding modes, where everything is paid at the end by construction.

What does this calculator not include?

It models the deposit itself and nothing around it. Early-withdrawal penalties, promotional or tiered rates, minimum balances, and account fees are not modeled; the rate is assumed fixed for the whole term. Deposit insurance limits and bank risk are outside its scope, as are currency movements if you deposit in a foreign currency. Tax is simplified to a single rate on gross interest at maturity, while some countries apply allowances, progressive rates, or different timing. Check the exact conditions of your offer before committing the money.