Calculate Your Savings Growth with Monthly Deposits
Figure out exactly how much cash you'll have saved up by plugging in your starting balance, monthly deposits, interest rate, and timeframe.
How to use: Free Savings Calculator with Monthly Contributions
This savings calculator works by taking your initial deposit and adding your monthly contributions, then applying compound interest to the whole pile each month. Here's the basic math: we start with what you've already got saved, add your monthly payment, calculate the monthly interest on that total, and repeat this process for however long you're planning to save. The formula compounds your interest monthly—meaning you earn interest on your interest—which is why your money grows faster than you might think. Most banks calculate interest daily or monthly, and this tool shows you the realistic picture of what that actually looks like over time. The longer your money sits, the more compound interest works its magic for you.
Let's say you've got $5,000 sitting in a high-yield savings account with a 4.5% annual rate, and you throw in $300 every month. After five years, you're looking at around $24,800—not bad, right? Here's another scenario: you start with $1,000, deposit $200 monthly, and your rate's 3.25%. In ten years, you'd have roughly $27,400. Or maybe you're more aggressive—you start with zero, sock away $500 a month in a CD ladder earning 4.75%, and after 15 years you've got about $108,000 to show for it. These numbers shift based on your exact interest rate and how often the bank compounds your interest, but you get the idea of how even modest monthly contributions add up seriously over time.
Don't assume your savings account rate stays the same forever—rates change constantly depending on what the Fed's doing. When you're comparing accounts, make sure you're looking at APY (annual percentage yield), not just APR, because APY already factors in compounding. A huge mistake people make is leaving money in a checking account earning basically zero percent when a high-yield savings account next door pays five times that. Also, if you're dealing with a CD, remember that penalty interest hits hard if you need the money early. Use this calculator to see how different interest rates and contribution amounts change your outcome—even a 0.5% difference compounds into real money over years.