# How to Make Financial Calculations using Python

What is the maximum amount you can borrow? How much will you have to pay back on your loan?

My car required a lot of warranty service last week, and I spent almost an entire weekday at the shop. I often strolled around the showroom where customers conversed with sales associates. The same two questions were asked over and over again. Python answers both issues.

We can compute two popular inquiries for anyone looking at their own money using Python’s Numpy financial package.

- What is the maximum amount I can borrow at Bridge – Bad Credit platform?
- What is the amount of my payment?

If you don’t have the Numpy-Financial library installed, you may use ‘pip’ to complete the operation. It is the only library other than standard Python that must be loaded for the computations in these examples.

## How Much Money Can I Borrow?

We need to start with three inputs when assessing how much you can afford to borrow:

1. The Rate of Interest

2. Loan Length & Payment Frequency

3. The Amount Due

Interest rates usually are established by the lending institution and are dependent on many criteria.

We’ll use a 5% interest rate in this example, but you should alter this to fit your needs. To acquire current averages in your region, conduct a fast search for “interest rates for house loans” or “interest rates for vehicle loans,” and then modify the rate to your credit position. The lower the interest rate you qualify for, the higher (better) your credit score is. Many websites will promote the lowest interest rates available to individuals with excellent credit scores. Keep in mind that these prices are generally for ideal scenarios, so your interest rate may be higher if you don’t have perfect credit. If you’re not sure what rate you’ll be able to borrow at, I recommend using the stated rate as a best-case scenario and adding a few percentage points to create a range.

There is probably a standard loan duration and payment frequency amount depending on the kind of loan. Home loans usually have a 15- or 30-year term with monthly payments. Payments on a car loan used to be made monthly for four years. Longer-term loans are becoming increasingly frequent these days. As a result, I recommend considering the following period durations for determining the kind of loan:

– Home loan with monthly payments for 15, 20, or 30 years

– Car Loan: Monthly payments for 4, 5, 6, or 7 years

The payment amount is the last input for our computation. What is your optimal payment amount after examining your monthly budget? Don’t know where to begin?

Many personal financial gurus suggest that total housing expenditures amount to less than 28 percent of your gross family income when applying for a home loan. This is the figure that banks frequently use in the approval process. HOA fees, insurance, taxes, and other expenditures linked with the house are all included in the 28 percent. Another popular computation is the maximum debt-to-income ratio, which divides your total debt (school loans, credit card debt, mortgage, etc.) by your income. In the United States, the Federal Housing Administration employs a maximum debt-to-income ratio of 43 percent, whereas many commercial lenders use a rate of roughly 36 percent.

While your lender’s maximum home loan amount may surpass 28 percent, and you may be able to acquire a loan with a more excellent debt-to-income ratio, these are reasonable rough figures to estimate your maximum monthly payment.

Maximum Monthly Home Loan Payment: $933.33 Maximum Monthly Debt: $1,433.33 For someone with a household income of $40,000, the total monthly home loan payment is $933.33, and the maximum monthly debt is $1,433.33.

With a household income of $80,000, the maximum monthly home loan payment is $1,866.66.

Monthly Maximum Debt: $2,866.66

Maximum Monthly Home Loan Payment: $2,800.00 Maximum Monthly Debt: $4,300.00 For someone with a household income of $120,000, the total monthly home loan payment is $2,800.00, and the maximum monthly debt is $4,300.00.

Loan Calculations in Python

After loading the library, we can determine how much you can afford to borrow by entering your monthly payment, interest rate, and loan period. Assume you’ve decided to borrow $24,945 to buy a new automobile. You anticipate that the interest rate will be 5%, and you want to borrow the money for six years.

What is the amount of my payment?

We use the inputs mentioned above and insert them into the NPF.pv() method to determine the monthly payment.

The yearly interest rate you’ll be paid on a loan is called the interest rate. It’s the nominal or declared rate. If the interest rate is 5%, we’ll write it down as.05. A 4.25 percent interest rate might be entered as.0425. We’ll enter.05 in the code block below since the rate we predicted is 5%.

Loan duration in years. A mortgage may be for 15, 20, or 30 years, but a car loan could be 4, 5, 6, or 7 years. A 42-month loan would be listed as 3.5. We’ll go to number six.

Payments per year would be 12 if you were making monthly payments. If you intend to pay in quarterly installments, this will be 4. The input will be 12 since most consumer loans are paid monthly.

The amount borrowed — The amount of money you’re going to borrow. The amount you will finance is $23,000, which should be entered as 23000. If the automobile costs $25,000 + $1,000 sales tax = $26,000 minus $3,000 down payment, the amount you will finance is $23,000, which should be entered as 23000. We’ll incorporate 24945 into our model.

In the script below, we’re borrowing $24,945, with monthly payments for six years at a 5% interest rate.