Savings Interest Calculator
How much will you earn on savings? Calculate simple and compound interest.
Savings Guide
Types of interest
Simple interest is calculated only from the initial principal for the entire saving period. Formula: principal × rate × time. Compound interest is calculated from principal plus previously earned interest — capitalization occurs. For long-term saving, the difference is enormous — after 10 years at 5% annual interest, compound interest yields over 12% more than simple interest. That's why Einstein called compound interest "the eighth wonder of the world."
Deposits and savings accounts
Term deposits are the simplest way to save with guaranteed returns. Banks offer a fixed rate for the entire deposit period — no worry about interest rate fluctuations. Savings accounts offer more flexibility (deposits and withdrawals possible), but usually with lower rates. In Poland, bank deposits are guaranteed by the Bank Guarantee Fund up to 100 000 euros, meaning full security. Compare offers from different banks before opening a deposit.
Real vs nominal interest
Nominal interest is the rate announced by banks. Real interest accounts for inflation — tells how much you'll actually gain after accounting for price increases. Formula: real = nominal minus inflation. With a 5% deposit and 3% inflation, real earnings are only 2%. That's why when choosing a deposit, check not only nominal interest but also estimated inflation and real return rate.
Alternative savings forms
Beyond deposits and savings accounts, there are other ways to grow savings: investment funds (offer higher potential returns but with risk), government bonds (including inflation-indexed), dividend-paying stocks (generate regular income), real estate (rental generates cash flow), or precious metals (crisis protection). Each has a different risk and return profile — matching to your goals and time horizon is important.