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 270 units (Dollar, Euro, Pound, etc.), from date: May 16, 2017, to date: Jun 16, 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%. Sep 24 11:26 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: Aug 22, 0544, to date: Mar 22, 2017, namely for a period of 537,849 days (17,671 Months), with an annual simple flat interest rate of 20% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:26 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: Aug 22, 0544, to date: Mar 22, 2017, namely for a period of 537,849 days (17,671 Months), with an annual simple flat interest rate of 20% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:26 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 25,692.92 units (Dollar, Euro, Pound, etc.), from date: Nov 15, 0294, to date: Sep 30, 2017, namely for a period of 629,267 days (20,674 Months and 15 Days), with an annual simple flat interest rate of 1% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:25 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 25,692.92 units (Dollar, Euro, Pound, etc.), from date: Nov 15, 0294, to date: Sep 30, 2017, namely for a period of 629,267 days (20,674 Months and 15 Days), with an annual simple flat interest rate of 1% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:25 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 4,500 units (Dollar, Euro, Pound, etc.), from date: Nov 01, 2013, to date: Jan 07, 2019, namely for a period of 1,893 days (62 Months and 6 Days), with an annual simple flat interest rate of 2% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:25 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 1,200 units (Dollar, Euro, Pound, etc.), from date: Mar 06, 0876, to date: Mar 06, 2021, namely for a period of 418,202 days (13,740 Months), with an annual simple flat interest rate of 12% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:24 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 1,200 units (Dollar, Euro, Pound, etc.), from date: Mar 06, 0876, to date: Mar 06, 2021, namely for a period of 418,202 days (13,740 Months), with an annual simple flat interest rate of 12% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:24 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 128,919.97 units (Dollar, Euro, Pound, etc.), from date: Mar 20, 0626, to date: Jun 28, 2017, namely for a period of 508,153 days (16,695 Months and 8 Days), with an annual simple flat interest rate of 4.75% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:24 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: Aug 02, 2000, to date: Aug 02, 2018, namely for a period of 6,574 days (216 Months), with an annual simple flat interest rate of 454% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:24 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 716 units (Dollar, Euro, Pound, etc.), from date: Jan 01, 2019, to date: Jan 01, 2020, namely for a period of 365 days (12 Months), with an annual simple flat interest rate of 8% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:24 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 21, 2019, to date: Feb 21, 2020, namely for a period of 396 days (13 Months), with an annual simple flat interest rate of 0.3% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:23 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 1,303,535 units (Dollar, Euro, Pound, etc.), from date: Nov 01, 0508, to date: Jun 30, 2017, namely for a period of 551,027 days (18,103 Months and 29 Days), with an annual simple flat interest rate of 6% if the commission fee (withdrawal or payment) is 0%. Sep 24 11:23 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.