Compound Interest Calculator with Contributions

Use our Compound Interest Calculator with Contributions to see what a starting amount grows to when you add money regularly — or how long it lasts when you take money out — with interest compounding yearly, every six months, quarterly, monthly, weekly or daily.

Each deposit earns interest from the day it goes in, and the interest is added to the balance on each compounding date, so it earns interest too. For example, $5,000 at 5% compounded monthly, plus $100 at the end of each month, grows to $23,763.28 in 10 years: $17,000 paid in and $6,763.28 of interest. Paying in at the start of each month instead adds another $64.70.

Your deposits don’t have to match the compounding. With interest added every six months and $150 paid in monthly, each deposit earns simple interest until the next compounding date. Choose withdrawals to see how long a balance lasts: $10,000 at 4% with $500 taken out each month runs out after 1 year 9 months.

The rate stays the same the whole time, and fees, taxes and inflation aren’t included, so treat the results as an estimate. To see how much compounding itself adds, use our Simple vs Compound Interest Calculator; for the contribution you’d need to reach a target, with fees and inflation, our Investment Calculator. If your rate changes over time, use our Variable Interest Rate Compound Calculator; to compare two savings accounts with different rates and fees, our Savings Interest Rate Comparison Calculator.