You will need
  • calculator;
  • - credit agreement or a description of the loan program.
The interest on the loan can be calculated in two ways: according to the actual number of days credit or at the rate of 30 days per month. Most often used the first method.
Must be taken from the loan agreement or ask the credit Manager interest rate, loan term, and amount of credit.
Further, the credit must be multiplied by interest rate divided by 100 and the number of days in the year (365 days in non-leap year) and multiplied by the number of days in the month and the term of the loan. For example, the rate on the loan is 12% per annum, the amount of 300 thousand and a term of 3 years, it turns out that the amount of interest for the first month will be 300 000 *(12/100)/(3*365)*30 (the number of days in month) = 986.3 R.

When monthly repayment of the loan the interest amount is recalculated based on the actual debt, and a large part of payments on percent for the first months.
In rare cases, the loan is repaid in a single payment. Then the interest and the principal amount shall be paid in a lump sum at the end of the period, and calculate them more easily. Multiply the interest rate by the loan amount and loan term. For example, the credit on 100 thousand rubles for one year at 15% annual interest on the loan will be = 100000*15/100= 15 000 RUB.
It remains to add additional fees and loan payments. For example, the monthly fee for account maintenance, credit review, insurance payments, which should add to the interest rate.