Compound Interest Calculator
Enter your principal, annual interest rate, time period, and how often interest compounds to calculate compound interest — interest earned on both your original principal and previously earned interest.
Save your student profile to track computations, past questions & GPA targets.
Enter principal, rate, and time to see the result.
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How It Works & Methodology
Compound interest is calculated on the principal plus all interest already earned, so it grows faster than simple interest over time. The formula is: A = P × (1 + r/n)^(n×t), where P is the principal, r is the annual interest rate as a decimal (rate % ÷ 100), n is the number of times interest compounds per year, and t is the time in years. A is the final amount after compounding, and the interest earned is Interest = A − P.
MyDelsu is an independent student platform and is not affiliated with DELSU administration. This tool is provided for guidance only — always verify results against your official transcript, result slip, or academic regulations.
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Frequently Asked Questions
What does compounding frequency mean?+
It's how many times per year your interest is calculated and added back to the principal: Annually = once a year (n=1), Semi-Annually = twice a year (n=2), Quarterly = four times a year (n=4), and Monthly = twelve times a year (n=12). The more frequently interest compounds, the faster your balance grows for the same annual rate.
Why does compound interest earn more than simple interest at the same rate?+
Because compound interest is calculated on your growing balance (principal + interest already earned), not just the original principal — so each period's interest is calculated on a slightly larger amount than the period before.
Which compounding frequency should I choose?+
Use whatever frequency matches your actual savings account, investment, or loan terms — check your bank or provider's documentation. If you're not sure, Annually is the most common default for illustrative calculations.
How much difference does compounding frequency actually make?+
For most everyday rates and time periods, the difference between quarterly and monthly compounding is fairly small — the bigger factor is always the interest rate and how long the money compounds for. Try switching frequencies above to see the exact difference for your numbers.
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