Simple Interest Calculator
A simple interest calculator computes financial interest earnings and total maturity balances without exponential compounding over days, months, or years. Using the formula Interest = Principal × Rate × Time (I = Prt), it confirms that depositing $1,000 at a 5% annual rate for 2 years yields $100 in interest.
By Maya Chen (Personal Finance Editor) · Reviewed by Daniel OkoroUpdated · Published
Principal
$
0
Rate
0%
Years
0yr
Compound:
FUTURE MATURITY VALUE
Interest earned: $0.00
How Does the Simple Interest Calculator Work?
- Multiply the principal amount by the annual interest rate divided by 100.
- Multiply that figure by the time in years.
- Add accrued interest to the principal to get the total maturity value.
What Is the Simple Interest Formula?
I = P × r × t ; Total = P + I
Principal times annual rate times time in years.
Variables
I:Total interest accrued
P:Principal initial sum
r:Annual interest rate decimal (Rate/100)
t:Time duration in years
How Do You Calculate Simple Interest Step by Step?
Investing $5,000 at 6% simple annual interest for 3 yearsPrincipal: $5,000
Rate: 6%
Years: 3
Interest: $5,000 × 0.06 × 3 = $900
Total balance: $5,000 + $900 = $5,900
Final Solution:$900 Interest ($5,900 Total)
Simple vs compound interest on $1,000 at 5% for 10 years
| Type | Formula | $1,000 at 5% x 10 yrs |
|---|---|---|
| Simple | I = P x r x t | $1,500.00 |
| Compound (annual) | A = P(1 + r)^t | $1,628.89 |
Simple Interest Questions and Answers
Simple interest is standard for short-term personal notes, auto loans, Treasury bills, and basic promissory agreements where interest is not reinvested into the principal.
Where Do These Simple Interest Standards Come From?
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