Math Calculators, Lessons and Formulas

It is time to solve your math problem

mathportal.org

# Simple interest calculator

Simple interest calculator finds the principal amount, interest amount and interest rate using simple interest formula. This calculator can help you deal with all kinds of simple interest problems. The calculator prints an easy-to-follow, step-by-step explanation.

Simple Interest Calculator
Find out the amount you'll receive after investing time.
help ↓↓ examples ↓↓ tutorial ↓↓
Hide steps

Get Widget Code

Simple Interest Calculator
In this calculator, you can select the value you want to find.
help ↓↓ examples ↓↓ tutorial ↓↓
Hide steps

Get Widget Code

working...
Examples
ex 1:
You put $1,000 into a bank account that pays 7% simple interest each year. You left the money in there for 3 years. Determine the interest earned and the total amount at the end of three years. ex 2: You deposit$12000 into a bank account with a monthly interest rate of 1.5%. You had the money in there for $210 days. Determine the amount of interest earned. ex 3: You put money into a bank account that pays 4% simple interest each year. After three years, you collected$72 in interest. How much was the deposit (principal)?
ex 4:
You put money into a bank account that pays 2% simple interest every six months. After 9 months, you received $15 in interest. How much was the principal? ex 5: You deposited$1000 into a bank account and received $50 in simple interest after three months. What was the interest rate? ex 6: You deposit$350 into a bank account with a monthly interest rate of 1.2%. Determine the length of time the money was in the bank if you received $9 in interest. Related calculators Find more worked-out examples in our database of solved problems.. ## Simple interest Simple interest is based only on the principal amount, unlike compound interest, where we use previously earned interest to calculate the next interest. For example if we invest \$100 for 3 years at an interest rate of 10% than we earn $10 each year. This calculator uses the following formula to solve simple interest problems: P is the principal. This is the total amount of money we invested. R is the ANNUAL rate of interest at which the money is given. T is the time duration in years for which the principal is invested. We will show how to use simple interest forumula on two examples. ### Calculate the interest earned on \$1200 if the rate is 6% over 3 years.

Step1 : Transform 6% into decimal

6% = 6 ÷ 100 = 0.06

Step2 : Apply above formula:

I = P × R × T = 1200 × 0.06 × 3 = 216

### You deposit \$800 into a bank account and received \$56 simple interest after 18 months. What is the interest rate per year?

Step1 : Transform 18 months into years

18 M = 18 ÷ 12 = 1.5 Y

Step2 : Apply above formula:

I = P × R × T
R = I ÷ ( P × T)
R = 56 ÷ (800 × 1.5)
R = 0.047
R = 4.7%

Search our database with more than 300 calculators
RESOURCES
441 955 071 solved problems
×
ans:
syntax error
C
DEL
ANS
±
(
)
÷
×
7
8
9
4
5
6
+
1
2
3
=
0
.