Compound Interest Calculator – Calculate CI Online
Principal Amount
Total interest
Total Amount
Related Tools
More tools in the same category
Other Tools
Popular tools from across A2Z
Rate this tool
Was this tool useful? Your feedback helps us improve it.
Quick answer
Compound interest is interest earned on both your original principal and the interest already accumulated. Enter a principal, annual rate, compounding frequency and term to see the future value instantly.
Key facts
- Uses the standard compound interest formula A = P(1 + r/n)^(nt)
- Supports 5 compounding frequencies: weekly, monthly, quarterly, half-yearly, and yearly
- Displays both the final amount and the total interest earned
- Runs entirely in your browser via JavaScript, no data sent to a server
- Free with no usage limit
What is this tool?
This calculator shows how an investment or loan grows when interest is compounded — that is, when each period's interest is added to the balance and itself earns interest in later periods.
How to use it
Enter your principal, the annual interest rate, the time period in years, and choose how often interest compounds (weekly, monthly, quarterly, half-yearly, or yearly), then click Calculate to see the results.- Enter the principal amount.
- Enter the annual interest rate as a percentage.
- Enter the time period in years.
- Select the compounding interval (weekly, monthly, quarterly, half-yearly, or yearly).
- Click Calculate to see the final amount and total interest.
Example
Example: a principal of 10,000 at 8% annual interest compounded yearly for 5 years grows to approximately 14,693.28, earning about 4,693.28 in compound interest.How it works
It applies the standard compound-interest formula:
A = P × (1 + r/n)n·t
- A — final amount
- P — principal
- r — annual interest rate (decimal)
- n — compounding periods per year
- t — years
Interest earned is A − P.
Common use cases
- Projecting savings-account or fixed-deposit growth
- Comparing yearly vs monthly compounding offers
- Estimating long-term investment outcomes
Benefits
Free, instant, and supports multiple compounding frequencies in a single calculator.Limitations
The projection assumes a constant interest rate and no additional deposits or withdrawals. Real products may charge fees, change rates or use different day-count conventions, so treat the result as an estimate rather than financial advice.
Privacy & your data
All calculations run in your browser. The amounts you enter are never transmitted to our servers.
Frequently asked questions
What is the difference between simple and compound interest?
Simple interest is paid only on the principal. Compound interest is paid on the principal plus previously earned interest, so the balance grows faster over time.
Why does compounding frequency matter?
How does compounding frequency affect the result?
More frequent compounding (monthly vs yearly) produces a slightly higher final amount at the same nominal rate, because interest starts earning interest sooner.
Does this account for taxes on interest earned?
Can I use this for loans as well as savings?
Yes — the same formula describes how a debt grows if unpaid, which makes the calculator useful for understanding loan balances too.
Is this guaranteed to match my bank's calculation exactly?
Is my data stored anywhere?
Last reviewed: