Steg-för-steg-instruktioner
Gather Your Inputs
First, identify the original loan amount, interest rate, and original monthly payment. Additionally, determine the extra monthly payment you want to make. In our example, the original loan amount is $200,000, the interest rate is 4% per annum, the original monthly payment is $955, and the extra monthly payment is $200.
Calculate the Monthly Interest Rate
Next, calculate the monthly interest rate by dividing the annual interest rate by 12. In our example, the monthly interest rate is 4%/12 = 0.003333.
Apply the Formula
Now, plug in the values into the formula M = P \* (1 + r)^n / ((1 + r)^n - 1) and solve for n. However, since this formula is for calculating the monthly payment, we will use a financial calculator or create a custom formula to solve for n with the extra payment. The result will give us the number of payments, which we can then use to calculate the payoff period.
Calculate the Payoff Period
After finding the number of payments, we can calculate the payoff period by dividing the number of payments by 12. For example, if the number of payments is 240, the payoff period is 240/12 = 20 years.
Use a Financial Calculator for Convenience
While doing the calculation by hand can be educational, using a financial calculator can be more convenient and less prone to errors. You can use an online mortgage payoff calculator to instantly get the result, including an amortization table and chart.
Avoid Common Mistakes
Common mistakes to avoid include incorrect input values, incorrect calculation of the monthly interest rate, and incorrect application of the formula. Double-check your inputs and calculations to ensure accuracy.
Introduction to Mortgage Payoff Calculator
The mortgage payoff calculator is a useful tool for determining how much time and interest can be saved by making extra monthly payments on a mortgage. In this guide, we will walk through the steps to calculate the mortgage payoff by hand, including the formula, a worked example, and common pitfalls to avoid.
Understanding the Formula
The formula to calculate the number of payments (n) is: n = -ln(1 - (r/P) * (P - (P * (1 + r)^(-n)))) where:
- n = number of payments
- r = monthly interest rate
- P = monthly payment However, to calculate the payoff period with extra payments, we can use the following formula: M = P * (1 + r)^n / ((1 + r)^n - 1) and then solve for n.
Worked Example
Let's say we have a $200,000 mortgage with a 30-year term and an interest rate of 4% per annum. The monthly payment (P) is $955. If we want to pay an extra $200 per month, the new monthly payment will be $1,155. To calculate the payoff period, we first need to calculate the monthly interest rate (r). The monthly interest rate is 4%/12 = 0.003333.
Using the formula, we can calculate the payoff period with the extra payment.