A home mortgage calculator gives us the amount a person pays monthly for the loan he/she owned from a financial institution.
The standard mortgage formula is
A = P(i(1+i)^n/((1+i)^n -1))
In the above formula
A = amount of the monthly payment
P = principal
I = rate of interest
N = number of years of the loan
If a person takes a loan of $100,000 at the rate of 5% per annum for 15 years, then the monthly payment is Calculation of I
I = .05/12 = .004167
And n = 12*15 = 180
In the calculation rate of interest is divided by to calculate the monthly interest rate and number of years are multiplied by 12 to calculate the number of months.
So putting the values in the above formula we get
A = $100,000(.004167 (1+.004167) ^180 / ((1+.004167) ^180 -1)) = $100,000 (.004167 * 2.1138)/1.1138 = $790.81
For calculating the interest paid to the financial institution over the life time of the loan we need to multiply the amount of monthly payment by the number of monthly payments and subtract the principal.
$790.81 *180 - $100,000 = $142,345.8 - $100,000 = $42,345.8
So the amount of interest paid to the financial institution monthly is $42,345.8
Interest in percentage |
15 year |
30 year |
Interest |
15 year |
30 year |
4 |
7.39688 |
4.77415 |
5 |
7.90794 |
5.36822 |
4.05 |
7.42196 |
4.80302 |
5.05 |
7.93401 |
5.39882 |
4.10 |
7.44709 |
4.83198 |
5.10 |
7.96013 |
5.42950 |
4.15 |
7.47227 |
4.86103 |
5.15 |
7.98629 |
5.46026 |
4.20 |
7.49750 |
4.89017 |
5.20 |
8.01251 |
5.49111 |
4.25 |
7.52278 |
4.91940 |
5.25 |
8.03878 |
5.52204 |
4.30 |
7.54811 |
4.94871 |
5.30 |
8.06509 |
5.55305 |
4.35 |
7.57349 |
4.97812 |
5.35 |
8.09145 |
5.58414 |
4.40 |
7.59892 |
5.00761 |
5.40 |
8.11787 |
5.61531 |
4.45 |
7.62440 |
5.03719 |
5.45 |
8.14433 |
5.64656 |
4.50 |
7.64993 |
5.06685 |
5.50 |
8.17083 |
5.67789 |
4.55 |
7.67551 |
5.09661 |
5.55 |
8.19739 |
5.70930 |
4.60 |
7.70114 |
5.12644 |
5.60 |
8.22400 |
5.74079 |
4.65 |
7.72682 |
5.15637 |
5.65 |
8.25065 |
5.77236 |
4.70 |
7.75254 |
5.18638 |
5.70 |
8.27735 |
5.80400 |
4.75 |
7.77832 |
5.21647 |
5.75 |
8.30410 |
5.83573 |
4.80 |
7.80414 |
5.24665 |
5.80 |
8.33090 |
5.86753 |
4.85 |
7.83002 |
5.27692 |
5.85 |
8.35774 |
5.89941 |
4.90 |
7.85594 |
5.30727 |
5.90 |
8.38464 |
5.93137 |
4.95 |
7.88191 |
5.33770 |
5.95 |
8.41158 |
5.96340 |
Using the above mortgage table we can determine the amount of the monthly payment without using the formula calculations; since the above interest rates are determined from the basic formula. But the table can be used to calculate the monthly payment per 1000 dollars of loan mortgage principal. And as seen above the interest rates are from 4% to 5.95% only.
For example, if we want to calculate the monthly payment for loan amount for above given example, the calculation should be like:
A = $100,000 (7.90794) / 10000 = $790.794
For a loan of $187,000 for 30 years at the rate of 5.5% interest the calculation and the monthly payment will be
$187,000 * 5.67789/1000 = $1061.77