Use this free daily compound interest calculator to work out how savings grow when interest is compounded every day. Enter the starting amount, the annual interest rate, and the number of days, and the daily compound interest calculator shows the final balance and the interest earned instantly — no sign-up, no account, and no personal information needed. Your numbers are calculated in your browser and are not sent to us.
Contents: Formula · How to use · Examples · Tips · FAQ · Related tools · Sources
No sign-up required. This daily compound interest calculator works in your browser, so the amounts you enter are not stored or sent to us. The result is an estimate for general planning, not financial advice.
How to Calculate Daily Compound Interest With This Daily Compound Interest Calculator
Daily compounding means interest is added to the balance every day, and the next day's interest is calculated on the new, slightly larger balance. Over a year, that gives a little more than yearly compounding at the same rate.
Final balance A = P × (1 + r ÷ 365)^days
Here P is the starting amount, r is the annual interest rate as a decimal, and days is the number of days. For example, $10,000 at 5% compounded daily for 365 days gives $10,000 × (1 + 0.05 ÷ 365)^365 = $10,512.67, so the interest earned is $512.67. Yearly compounding at the same rate would give only $10,500.00, so daily compounding adds $12.67 here.
How to Use the Daily Compound Interest Calculator
Type the starting amount into the first box, the annual interest rate as a percentage into the second box — for 5%, type 5, not 0.05 — and the number of days into the third box. Tap Calculate Daily Compound Interest to see the final balance and the interest earned.
For a full year, type 365 days; for six months, type about 180 days. If you want yearly, half-yearly, quarterly, or monthly compounding instead, use the Compound Interest Calculator, which covers those frequencies. This daily compound interest calculator is the daily-only version, kept separate so the result is easy to check.
Daily Compound Interest Calculator Examples
Example 1 — $10,000 at 5% daily for 365 days. Final balance = $10,512.67. Interest earned = $512.67.
Example 2 — $5,000 at 4% daily for 180 days. Final balance = $5,099.62. Interest earned = $99.62.
Example 3 — $1,000 at 6% daily for 90 days. Final balance = $1,014.90. Interest earned = $14.90.
These daily compound interest calculator examples show that daily compounding helps most over longer periods. Over 90 days, the extra interest over simple interest is small, but over a full year it is easier to see.
Daily Compound Interest Calculator Tips
Compare accounts on the final balance, not just the headline rate, because daily compounding beats yearly compounding by a small amount at the same rate. Remember that this result is before tax and before fees, and it assumes the rate stays the same and no money is added or withdrawn.
For a plain explanation of compound interest, see Investopedia's guide to compound interest. If you are saving regularly rather than once, a single starting amount will understate the result, because new deposits also earn interest after they are added.
Daily Compound Interest Calculator FAQ
What does a daily compound interest calculator do? A daily compound interest calculator works out how a starting amount grows when interest is compounded every day over a set number of days.
How is this different from the compound interest calculator? The Compound Interest Calculator offers yearly, half-yearly, quarterly, and monthly compounding over years. This daily compound interest calculator compounds every day and takes days as the time input.
How do I calculate daily compound interest by hand? Use A = P × (1 + r ÷ 365)^days, then subtract P to get the interest earned. The daily compound interest calculator does this arithmetic for you.
Why 365 days? Most daily compounding calculations use 365 days in a year. Some banks use 360 days, which gives a slightly different result, so check your account's terms if you need an exact figure.
Does daily compounding make a big difference? Only a small one at ordinary rates. At 5% for one year, daily compounding adds $12.67 on $10,000 compared with yearly compounding.
Try the Compound Interest Calculator for yearly, half-yearly, quarterly, and monthly compounding, the Interest Calculator for simple and compound interest kept separate, the Home Loan Calculator for monthly loan payments, and the Discount Calculator for a sale price. Return to the PDGPT homepage to browse all free calculators by category. This calculator uses the daily compound interest formula A = P x (1 + r / 365)^days, with interest earned as A - P. Results are estimates for general planning, not financial advice. Last updated: October 28, 2026.Related Tools
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