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हिन्दीCompound Interest Calculator
This Compound Interest Calculator can help determine the compound interest accumulation and final balances on both fixed principal amounts and additional periodic contributions. There are also optional factors available for consideration, such as the tax on interest income and inflation.
Modify the values and click the calculate button to use
Results
| Year | Deposit | Interest | Ending balance |
|---|
About Interest Calculator
Interest is the compensation paid by the borrower to the lender for the use of money as a percent or an amount. The concept of interest is the backbone behind most financial instruments in the world.
There are two distinct methods of accumulating interest, categorized into simple interest or compound interest.
Simple Interest
The following is a basic example of how interest works. Derek would like to borrow $100 (usually called the principal) from the bank for one year. The bank wants 10% interest on it. To calculate interest:
$100 × 10% = $10
This interest is added to the principal, and the sum becomes Derek’s required repayment to the bank one year later.
$100 + $10 = $110
Derek owes the bank $110 a year later, $100 for the principal and $10 as interest.
Compound Interest
Compounding interest requires more than one period, so let’s go back to the example of Derek borrowing $100 from the bank for two years at a 10% interest rate. For the first year, we calculate interest as usual.
$100 × 10% = $10
This interest is added to the principal, and the sum becomes Derek’s required repayment to the bank for that present time.
$100 + $10 = $110
However, the year ends, and in comes another period. For compounding interest, rather than the original amount, the principal + any interest accumulated since is used. In Derek’s case:
$110 × 10% = $11
Derek’s interest charge at the end of year 2 is $11. This is added to what is owed after year 1:
$110 + $11 = $121
When the loan ends, the bank collects $121 from Derek instead of $120 if it were calculated using simple interest instead. This is because interest is also earned on interest.
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How to Use the Interest Calculator
- Enter Your Investment Details
- Initial Investment: Enter the starting amount of money you’re investing.
- Annual Contribution: Add any yearly deposits you plan to make.
- Contribution Timing: Choose whether deposits happen at the beginning or end of each period.
- Set Interest & Timeframe
- Interest Rate (%): Input the expected annual interest rate.
- Compound Frequency: Select how often interest compounds (yearly, monthly, daily, etc.).
- Investment Length: Enter years and months for your investment horizon.
- Adjust for Taxes & Inflation (Optional)
- Tax Rate (%): Account for taxes on interest earnings.
- Inflation Rate (%): Adjust for inflation to see real purchasing power.
- Click “Calculate”
- Instantly view your ending balance, total interest earned, and growth breakdown.
- See an interactive chart showing contributions vs. interest growth.
- Check the annual/monthly schedule for detailed projections.
- Explore Results & Tips
- Investment Advice: Get personalized tips based on your inputs.
- Print/Save: Export or print results for future reference.
Pro Tips
- For long-term growth, increase compound frequency (e.g., monthly > yearly).
- Use the inflation adjustment to compare real returns.
- Switch between Annual/Monthly tabs to see detailed timelines.
This tool helps you visualize wealth growth for savings, retirement, or loans. Try different scenarios to optimize your financial plan!
Frequently Asked Questions (FAQs) – Interest Calculator
1. What does this calculator do?
This tool calculates compound interest on investments, savings, or loans, accounting for:
✅ Initial deposit
✅ Regular contributions
✅ Interest compounding (daily, monthly, yearly)
✅ Taxes & inflation adjustments
2. How does compound interest work?
Compound interest means you earn interest on both your initial investment and accumulated interest over time. The more frequently interest compounds (e.g., monthly vs. yearly), the faster your money grows.
Example:
- $10,000 at 5% annual interest = $16,288.95 in 10 years (compounded monthly).
3. Should I contribute at the beginning or end of the period?
- Beginning: Maximizes growth (interest applies to deposits sooner).
- End: Standard for most savings accounts.
4. Why include taxes and inflation?
- Tax Rate: Reduces net returns (e.g., 25% tax on interest).
- Inflation: Shows real purchasing power (e.g., $100 today ≠ $100 in 10 years).
5. What’s the difference between simple and compound interest?
| Simple Interest | Compound Interest |
|---|---|
| Earns interest only on the original principal | Earns interest on principal + accumulated interest |
| Linear growth | Exponential growth |
| Rarely used in real-world investing | Standard for savings, loans, and investments |
6. How accurate are the results?
- Estimates only: Assumes fixed interest rates and regular contributions.
- Market fluctuations (e.g., stock returns) aren’t accounted for.
7. Can I use this for loans or debt?
Yes! Input:
- Initial Investment = Loan amount
- Interest Rate = Loan APR
- Contributions = Monthly payments
The calculator shows total interest paid and payoff timeline.
8. Why does my bank’s interest differ slightly?
- Banks may use daily compounding with slight variations.
- Fees or promotional rates aren’t reflected here.
9. How do I maximize returns?
- Increase contributions (even small amounts add up!).
- Choose higher compounding frequencies (e.g., monthly > yearly).
- Reinvest dividends/interest for compounding benefits.
10. Can I save or print my results?
Yes! Click the “Print” button to export your calculation.