Simple Interest Calculator
Calculate simple interest accrued on principal over a time period, showing total interest and final maturity values.
Interest Settings
Accrued Wealth Summary
What is the Simple Interest Calculator?
The Simple Interest Calculator is a fundamental financial utility designed to compute the interest accrued on a principal sum over a specific time period. Unlike compound interest, simple interest is calculated solely as a percentage of the original principal amount, meaning the interest earned does not compound over successive terms. This calculator supports custom time intervals in years, months, or days, making it ideal for short-term loans, basic savings accounts, and promissory notes. You can review core interest concepts and calculators on official economic and financial portals: the US Securities and Exchange Commission (SEC), the Securities and Exchange Board of India (SEBI), the European Securities and Markets Authority (ESMA), the Financial Conduct Authority (FCA), the Securities and Exchange Commission of Pakistan (SECP), the Bangladesh Securities and Exchange Commission (BSEC), and the Capital Markets Board of Turkey (SPK).
Formula & Calculation Method
Simple interest calculations apply a direct multiplier based on principal, rate, and tenure: 1. **Simple Interest (I)**: $$I = P \times \left(\frac{R}{100}\right) \times t$$ Where: - $P$ is the principal investment or loan amount. - $R$ is the annual simple interest rate. - $t$ is the tenure expressed as a fraction of a year. 2. **Tenure Fraction ($t$)**: - If tenure is in Years: $t = \text{Tenure}$ - If tenure is in Months: $t = \frac{\text{Tenure}}{12}$ - If tenure is in Days: $t = \frac{\text{Tenure}}{365}$ 3. **Maturity Amount (A)**: $$A = P + I$$
Worked Example Calculation
Let's analyze a simple interest calculation example. Suppose you deposit $10,000 for 18 months at an annual simple interest rate of 6%. 1. **Principal (P)** = $10,000. 2. **Interest Rate (R)** = 6%. 3. **Tenure (t)** = 18 months, which equals: $$t = \frac{18}{12} = 1.5 \text{ years}$$ 4. **Interest Earned (I)**: $$I = 10,000 \times 0.06 \times 1.5 = \text{S}900$$ 5. **Maturity Value (A)**: $$A = 10,000 + 900 = \text{S}10,900$$ At the end of the 18-month tenure, the total amount payable is $10,900, comprising the $10,000 principal and $900 in simple interest.
Frequently Asked Questions (FAQ)
What is the main difference between simple and compound interest?
Simple interest is calculated only on the initial principal amount throughout the tenure. Compound interest is calculated on the principal plus any accumulated interest from prior periods, leading to exponential growth.
Under what circumstances is simple interest commonly used?
Simple interest is typically used for short-term financial instruments, car loans, personal loans, certificates of deposit (CD) with fixed monthly payouts, and standard retail bank savings accounts.
Does simple interest earn more than compound interest?
No. For any interest rate and tenure greater than one compounding period, compound interest will always yield higher returns than simple interest because of the compounding effect.
How is tenure in days calculated?
When you select tenure in days, the calculator divides the number of days by 365 to determine the exact fraction of a year ($t$), which represents standard bank interest day-count conventions.
Are simple interest earnings taxable?
Yes, interest income earned from simple interest loans or savings deposits is generally treated as taxable income under local tax regulations and must be reported on tax returns.
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