Simple (Flat Rate) Interest Calculator: Calculate the Sum of Money Earned by a Principal Amount of Money (Initial Starting Amount Lent, Deposited or Borrowed) by the Annual Simple Interest Rate, Investment Duration Period and Transaction Fee

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

The latest calculated simple flat rate interest values

Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 500 units (Dollar, Euro, Pound, etc.) for a period of 50 days (2 Months without 11 Days), with an annual simple flat interest rate of 2%. Jul 15 18:03 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 456,000,000 units (Dollar, Euro, Pound, etc.) for a period of 365 days (12 Months), with an annual simple flat interest rate of 10%. Jul 15 18:02 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 100 units (Dollar, Euro, Pound, etc.) for a period of 730 days (24 Months), with an annual simple flat interest rate of 516%. Jul 15 18:00 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 5 units (Dollar, Euro, Pound, etc.) for a period of 31 days, with an annual simple flat interest rate of 100%. Jul 15 18:00 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 1,242 units (Dollar, Euro, Pound, etc.) for a period of 184 days (6 Months), with an annual simple flat interest rate of 24%. Jul 15 18:00 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 0 units (Dollar, Euro, Pound, etc.) for a period of 624,352 days (20,513 Months), with an annual simple flat interest rate of 0%. Jul 15 17:59 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 15,583 units (Dollar, Euro, Pound, etc.) for a period of 2 days, with an annual simple flat interest rate of 5%. Jul 15 17:58 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 10,000 units (Dollar, Euro, Pound, etc.) for a period of 1,826 days (60 Months), with an annual simple flat interest rate of 8%. Jul 15 17:56 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 1,000,000,000,000 units (Dollar, Euro, Pound, etc.) for a period of 181,282 days (5,956 Months), with an annual simple flat interest rate of 0%. Jul 15 17:54 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 100 units (Dollar, Euro, Pound, etc.) for a period of 549,690 days (18,060 Months), with an annual simple flat interest rate of 3%. Jul 15 17:54 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 10,000 units (Dollar, Euro, Pound, etc.) for a period of 1,857 days (61 Months), with an annual simple flat interest rate of 9%. Jul 15 17:53 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 0 units (Dollar, Euro, Pound, etc.) for a period of 427,363 days (14,041 Months), with an annual simple flat interest rate of 20%. Jul 15 17:49 UTC (GMT)
Calculate the simple (flat rate) interest earned by a principal (initial amount of money lent, deposited or borrowed) of 212 units (Dollar, Euro, Pound, etc.) for a period of 1,126 days (37 Months), with an annual simple flat interest rate of 2%. Jul 15 17:49 UTC (GMT)
All the 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.