Introduction
This daily compound interest calculator shows you how your money grows when interest is added to your balance every day. Unlike simple interest, which only earns on your starting amount, compound interest earns interest on your interest too. That means your savings grow faster over time. The more days that pass, the bigger the effect.
Use this tool to enter your starting deposit, interest rate, and how long you plan to save. You can also add regular deposits or withdrawals, pick which days earn interest, and choose how often interest compounds. The calculator gives you a final balance, a full breakdown by month or year, a growth chart, and a step-by-step solution so you can see exactly how the math works.
Plan a savings goal, compare bank accounts, or learn how compound interest works: this calculator shows your results.
How to Use Our Daily Compound Interest Calculator
Enter your deposit amount, interest rate, and time period to see how your money grows with daily compounding. The calculator will show your final balance, total interest earned, a growth chart, and a full breakdown table.
Currency Symbol: Pick the currency you want to use, such as USD, EUR, or GBP. Choose "None" if you are tracking points, tokens, or crypto.
Initial Deposit: Type in the amount of money you are starting with before any interest is added.
Interest Rate (%): Enter the interest rate you earn. This is the number your bank or investment gives you.
Rate Period: Choose whether your interest rate is a daily, weekly, monthly, quarterly, or annual rate. Most banks use an annual rate.
Compounding Frequency: Select how often interest is calculated and added to your balance. "Daily (365/year)" is the most common choice for daily compound interest. Pick "Daily (360/year)" for the bank convention. Choose "Custom" to set your own number of compounding periods per year.
Investment Duration: Enter how long you plan to invest using the years, months, and days fields. You can use any combination of all three.
Start Date: Optionally pick a start date for your investment. This lets the calculator use exact calendar days and apply holiday or weekend rules.
Daily Reinvestment Rate: Choose what percent of each day's earned interest gets added back to your balance. Set it to 100% to reinvest all interest. A lower number means you take some interest out as cash each day.
Compounding Days: Check or uncheck days of the week to control which days earn interest. Use the "Exclude Weekends" button to quickly remove Saturdays and Sundays.
Exclude U.S. Federal Holidays: Set this to "Yes" if you want to skip federal holidays as compounding days. This only works when a start date is set.
Additional Cash Flows: Choose "None" if you only want to calculate growth on your initial deposit. Pick "Deposits Only," "Withdrawals Only," or "Both" to add regular contributions or withdrawals.
Deposit Amount & Frequency: If deposits are turned on, enter how much you add and how often (daily, weekly, monthly, etc.). Choose whether deposits happen at the beginning or end of each period.
Annual Deposit Increase: If your deposits grow each year, enter the increase as a percent or a fixed dollar amount.
One-Time Lump Sum Deposit: Enter an extra one-time deposit amount and the date it will be added. The date must fall within your investment window.
Withdrawal Type: If withdrawals are turned on, choose "Fixed Amount" to take out a set dollar amount, "% of Balance" to withdraw a share of your total balance, or "% of Earnings" to withdraw a share of interest earned.
Withdrawal Amount & Frequency: Enter how much you withdraw and how often. You can also set an annual increase percentage if your withdrawals grow over time.
Press the Calculate button to see your results. Press Reset to clear all fields and start over. Use the chart and table toggle buttons to switch between monthly and yearly views of your growth.
What Is Daily Compound Interest?
Daily compound interest is when a bank or investment adds interest to your balance every single day. Once that interest is added, it becomes part of your new balance. The next day, you earn interest on the original money plus the interest from the day before. This cycle repeats each day, so your money grows faster over time compared to simple interest, which only pays you on your starting amount.
How Daily Compound Interest Works
The basic formula for compound interest is A = P(1 + r/n)nt. Here, P is the money you start with (your principal), r is the annual interest rate as a decimal, n is how many times interest compounds per year, and t is the number of years. For daily compounding, n is 365 (or 360 if your bank uses that convention). The result, A, is your total balance at the end.
For example, if you deposit $10,000 at a 5% annual rate compounded daily for 5 years, you earn more than you would with monthly or yearly compounding. That is because interest is calculated and added to your balance 365 times a year instead of 12 or 1.
Why Daily Compounding Matters
The more often interest compounds, the more you earn. Daily compounding gives you the highest growth among standard compounding frequencies. The difference between daily and monthly compounding may look small over one year, but it adds up over many years. This effect is sometimes called the power of compounding.
APR vs. APY
Two rates you will often see are APR (Annual Percentage Rate) and APY (Annual Percentage Yield). APR is the stated rate before compounding is factored in. APY is the actual rate you earn after compounding does its work.1 When interest compounds daily, the APY is always a little higher than the APR. For instance, a 5.00% APR compounded daily gives you an APY of about 5.13%.
Where Daily Compound Interest Is Used
- Savings accounts – Most banks compound interest on savings accounts daily.
- Money market accounts – These also typically use daily compounding.
- Certificates of deposit (CDs) – Many CDs compound daily, though some compound monthly.
- Loans and credit cards – Credit card companies often charge interest that compounds daily, which means debt can grow quickly if unpaid.2
- Crypto and DeFi – Some decentralized finance protocols calculate yield on a daily basis.
Tips to Make the Most of Compound Interest
Start early. The longer your money compounds, the bigger the effect. Even small deposits grow significantly over many years. Add money regularly. Making monthly or weekly deposits increases the base that earns interest each day. Leave your earnings alone. Withdrawing interest slows down compounding because there is less money in the account to grow. Compare APYs. When choosing between accounts, always compare the APY, not just the APR, so you see the true return after compounding. Planning for long-term goals like retirement or reaching financial independence becomes much easier when you harness daily compounding from the start.