Simple flat rate interest calculator: calculate the due interest on an amount of money lent, deposited or borrowed by the interest rate, principal (starting amount), duration and additional transactional fees (withdrawal, payment in advance)

Calculate simple flat rate interest on a principal borrowed, lent

Simple flat rate interest = (Principal × Annual simple flat interest rate × Duration in days) ÷ Number of days in a year

Latest calculated simple flat rate interest values

Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 400 units (Dollar, Euro, Pound, etc.), from date: May 07, 0960, to date: Apr 07, 2017, namely for a period of 386,031 days (12,683 Months), with an annual simple flat interest rate of 29% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 3,125 units (Dollar, Euro, Pound, etc.), from date: Jun 20, 0652, to date: Apr 27, 2016, namely for a period of 498,137 days (16,366 Months and 7 Days), with an annual simple flat interest rate of 8% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 16,465 units (Dollar, Euro, Pound, etc.), from date: Oct 01, 2019, to date: Oct 01, 2019, namely for a period of 0 days, with an annual simple flat interest rate of 1.35% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 25,000 units (Dollar, Euro, Pound, etc.), from date: Feb 26, 2018, to date: Mar 26, 2018, namely for a period of 28 days, with an annual simple flat interest rate of 15% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 4,000 units (Dollar, Euro, Pound, etc.), from date: Jan 09, 2019, to date: Feb 09, 2019, namely for a period of 31 days, with an annual simple flat interest rate of 9% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 10,000 units (Dollar, Euro, Pound, etc.), from date: Nov 19, 2017, to date: Nov 19, 2018, namely for a period of 365 days (12 Months), with an annual simple flat interest rate of 12% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 3,500 units (Dollar, Euro, Pound, etc.), from date: Dec 12, 2013, to date: May 31, 2019, namely for a period of 1,996 days (65 Months and 19 Days), with an annual simple flat interest rate of 0.02% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:41 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 30,000 units (Dollar, Euro, Pound, etc.), from date: Jun 30, 2019, to date: Jun 30, 2023, namely for a period of 1,461 days (48 Months), with an annual simple flat interest rate of 2% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:40 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 4,000 units (Dollar, Euro, Pound, etc.), from date: Mar 14, 2018, to date: Apr 14, 2018, namely for a period of 31 days, with an annual simple flat interest rate of 0.7% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:40 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 100 units (Dollar, Euro, Pound, etc.), from date: May 25, 2017, to date: Jun 25, 2017, namely for a period of 31 days, with an annual simple flat interest rate of 3% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:40 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 136 units (Dollar, Euro, Pound, etc.), from date: Sep 16, 2017, to date: Oct 16, 2018, namely for a period of 395 days (13 Months), with an annual simple flat interest rate of 15% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:40 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 338 units (Dollar, Euro, Pound, etc.), from date: Mar 28, 2017, to date: Mar 28, 2027, namely for a period of 3,652 days (120 Months), with an annual simple flat interest rate of 4.22% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:40 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 7,000 units (Dollar, Euro, Pound, etc.), from date: Apr 15, 2019, to date: Apr 15, 2020, namely for a period of 366 days (12 Months), with an annual simple flat interest rate of 5% if the commission fee (withdrawal or payment) is 0%. Apr 05 09:39 UTC (GMT)
All users calculated simple flat rate interest values


Simple flat rate interest.

Interest

  • When someone lends money to someone else, the borrower usually pays a fee to the lender. So the due interest is a sum paid or charged for the use of money or for borrowing money. The interest depends on: 1) the period of the loan 2) the amount of money lent or borrowed (called principal) and 3) the interest rate (the percentage of the principal charged as interest).
  • For example, for some bank deposits is not uncommon to pay an interest rate of 3.5% on the principal, annualy. Banks are also using these temporarily owned amounts of money by introducing them back into the cash flow circuit or are granting loans (for investments, for example) on which they are again charging interest.

Annual simple flat interest rate

  • The simple annual interest rate, or the percentage of the principal charged as interest for a period of one year, shows us that for an amount of 100 units (ex: Dollar, Euro, Yen, Pound, Franc), in a year, the interest is calculated as a percentage p% of the principal: I = p% × 100 units.
  • A deposit of S units generates a one year simple interest of: I = S × p% units, and in n years, the same deposit of S units generates an interest of: I = S × p% × n units.

Annual simple flat rate interest formula:

  • I = S × p% × n

  • I = n years simple flat rate interest charged
  • S = initial amount (principal)
  • p% = annual simple flat interest rate (percentage of the principal charged as interest)
  • n = number of years of the lending or borrowing the money

Examples of how the simple flat rate interest formula works:

  • 1) What interest, I, generates in n = 5 years a principal of S = 20,000 units if the annual simple flat interest rate is p% = 3.5%?
    Answer:
    I = S × p% × n = 20,000 × 3.5% × 5 = 20,000 × 3.5 ÷ 100 × 5 = 1,000 × 3.5 = 3,500 units
  • 2) What is the simple flat interest rate, p%, if a principal of S = 12,000 units is charged a n = 6 years interest of I = 2,880 units?
    Answer:
    I = S × p% × n =>
    p% = I ÷ (S × n) = 2,880 ÷ (12,000 × 6) = 0.04 = 4%.

Annual simple flat rate interest formula calculated for a period of n years:

  • Interest, I = S × p% × n
  • Principal, S = I ÷ (p% × n)
  • Interest rate, p% = I ÷ (S × n)
  • Number of years (period): n = I ÷ (S × p%)

Annual simple flat rate interest formula calculated for a period of m months:

  • Interest, I = (S × p% × m) ÷ 12
  • Principal, S = (12 × I) ÷ (p% × m)
  • Interest rate, p% = (12 × I) ÷ (S × m)
  • Number of months of the period, m = (12 × I) ÷ (S × p%)

Annual simple flat rate interest formula calculated for a period of d days:

  • Interest, I = (S × p% × d) ÷ 365
  • Principal, S = (365 × I) ÷ (p% × d)
  • Simple flat interest rate, p% = (365 × I) ÷ (S × d)
  • Number of days of the period, d = (365 × I) ÷ (S × p%)

More examples of how the simple flat rate interest formula works:

  • 1) Calculate the due interest on a principal of S = 400 units in m = 5 months, with a simple flat interest rate of p% = 4%.
    Answer:
    I = (S × p% × m) ÷ 12 = (400 × 4% × 5) ÷ 12 = (400 × 4 ÷ 100 × 5) ÷ 12 = 16 × 5 ÷ 12 = 20 ÷ 3 = 6.67 units
  • 2) Calculate the due interest generated by a principal of S = 400 units in m = 5 months if the simple flat interest rate of p% = 4.5%.
    Answer:
    I = (S × p% × m) ÷ 12 = (400 × 4.5% × 5) ÷ 12 = (400 × 4.5 ÷ 100 × 5) ÷ 12 = 18 × 5 ÷ 12 = 15 ÷ 2 = 7.5 units.