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 1,200 units (Dollar, Euro, Pound, etc.), from date: Aug 01, 0322, to date: Jan 01, 2018, namely for a period of 619,240 days (20,345 Months), with an annual simple flat interest rate of 5% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 320,000 units (Dollar, Euro, Pound, etc.), from date: Jun 30, 0918, to date: May 30, 2017, namely for a period of 401,371 days (13,187 Months), with an annual simple flat interest rate of 1.8% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 320,000 units (Dollar, Euro, Pound, etc.), from date: Jun 30, 0918, to date: May 30, 2017, namely for a period of 401,371 days (13,187 Months), with an annual simple flat interest rate of 1.8% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 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: Sep 26, 0948, to date: Oct 26, 2018, namely for a period of 390,839 days (12,841 Months), with an annual simple flat interest rate of 2.75% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 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: Sep 26, 0948, to date: Oct 26, 2018, namely for a period of 390,839 days (12,841 Months), with an annual simple flat interest rate of 2.75% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 1 units (Dollar, Euro, Pound, etc.), from date: Mar 11, 2018, to date: Feb 11, 2062, namely for a period of 16,043 days (527 Months), with an annual simple flat interest rate of 0.03% if the commission fee (withdrawal or payment) is 970%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 10 units (Dollar, Euro, Pound, etc.), from date: Dec 15, 0302, to date: Jan 15, 2015, namely for a period of 625,327 days (20,545 Months), with an annual simple flat interest rate of 3.5% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 820 units (Dollar, Euro, Pound, etc.), from date: Oct 10, 2018, to date: Nov 10, 2023, namely for a period of 1,857 days (61 Months), with an annual simple flat interest rate of 0.26% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 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 26, 0456, to date: Sep 26, 2018, namely for a period of 570,539 days (18,745 Months), with an annual simple flat interest rate of 2.33% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 622 units (Dollar, Euro, Pound, etc.), from date: Jun 23, 2020, to date: Sep 23, 2020, namely for a period of 92 days (3 Months), with an annual simple flat interest rate of 478% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 0 units (Dollar, Euro, Pound, etc.), from date: Jun 19, 0486, to date: May 19, 2018, namely for a period of 559,520 days (18,383 Months), with an annual simple flat interest rate of 8% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:19 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: Oct 28, 0498, to date: Sep 28, 2016, namely for a period of 554,408 days (18,215 Months), with an annual simple flat interest rate of 3% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:18 UTC (GMT)
Calculate due interest earned by a principal (initial amount of money lent, deposited or borrowed) of 12,000 units (Dollar, Euro, Pound, etc.), from date: Jan 08, 2018, to date: Oct 08, 2034, namely for a period of 6,117 days (201 Months), with an annual simple flat interest rate of 15% if the commission fee (withdrawal or payment) is 0%. Feb 24 20:18 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.