A daily interest calculator shows how much interest accrues each day on a savings balance, loan or credit card. Enter the balance, annual interest rate and number of days, and it calculates daily interest and the total over the period, with or without compounding.
For simple daily interest, the formula is: daily interest = balance × (annual rate ÷ 365). For example, $10,000 at 5 percent earns about $1.37 per day, or about $41 in 30 days. For daily compounding, the balance grows each day: A = P(1 + r/365)^days. Over a year, $10,000 at 5 percent compounded daily grows to about $10,513.
Credit cards usually calculate interest using a daily periodic rate (APR ÷ 365) applied to your average daily balance. That’s why carrying a balance gets expensive quickly: a $3,000 balance at 24 percent APR accrues about $1.97 in interest every day. Paying your balance in full each month avoids interest on most cards.
Tips: some lenders use 360 days instead of 365 for daily calculations, which slightly increases daily interest. Mortgage payoffs and student loans often quote a “per diem” amount, which is the daily interest. Use APY to compare savings accounts, since it includes compounding.
How to use the Daily Interest Calculator on Minedit: enter your values in the fields, press calculate, and review the step-by-step breakdown under the result. If something looks off, change one input at a time to see how it affects the answer, which is also a great way to learn the math behind it.
Why use an online Daily Interest Calculator: it saves time, avoids simple arithmetic mistakes and shows each step, so you can check your homework, plan a project or make a decision with confidence. Bookmark the page so it’s ready the next time you need it.
Learn more about compounding on Wikipedia’s compound interest article. Find savings interest, CD and minimum payment calculators on Minedit.