30 Year Mortgage Calculator Usa

Use this 30-year mortgage calculator to estimate your monthly payments for a home loan in the USA. The calculator provides an amortization schedule and helps you understand how interest rates affect your mortgage payments.

How to Use This Calculator

To calculate your 30-year mortgage payment:

Enter the loan amount (the total amount you want to borrow).
Input your current interest rate (annual percentage rate).
Click "Calculate" to see your estimated monthly payment.

The calculator will display your monthly payment, total interest paid over the loan term, and an amortization chart showing how your loan balance decreases each year.

Mortgage Formula

The monthly mortgage payment is calculated using the following formula:

Mortgage Payment Formula

M = P [ i(1 + i)ⁿ ] / [ (1 + i)ⁿ - 1 ]

Where:

M = Monthly payment
P = Principal loan amount
i = Monthly interest rate (annual rate divided by 12)
n = Number of payments (loan term in years × 12)

This formula uses the standard amortization method where equal payments are made each month, including principal and interest.

Worked Example

Let's calculate a 30-year mortgage for $300,000 at a 6% annual interest rate.

Principal (P) = $300,000
Annual interest rate = 6% → Monthly rate (i) = 6% ÷ 12 = 0.5%
Loan term (n) = 30 years × 12 = 360 months

Plugging these values into the formula:

Calculation Steps

M = $300,000 [ 0.005(1 + 0.005)³⁶⁰ ] / [ (1 + 0.005)³⁶⁰ - 1 ]

M ≈ $300,000 [ 0.005 × 1.005³⁶⁰ ] / [ 1.005³⁶⁰ - 1 ]

M ≈ $300,000 [ 0.005 × 31.88 ] / [ 31.88 - 1 ]

M ≈ $300,000 [ 0.1594 ] / 30.88

M ≈ $300,000 × 0.00516 / 30.88

M ≈ $1,593.65 / 30.88 ≈ $1,593.65

Your estimated monthly payment would be approximately $1,593.65.

Note

This is an estimate. Actual payments may vary based on your lender's specific calculations and any additional fees or closing costs.

Frequently Asked Questions

What is a 30-year mortgage?: A 30-year mortgage is a home loan that is repaid over 30 years (360 months) with equal monthly payments. It's the most common type of mortgage in the USA.
How does the interest rate affect my mortgage payment?: A higher interest rate means you'll pay more in interest over the life of the loan, increasing your total payments. Conversely, a lower rate reduces your total interest costs.
What is the difference between fixed and adjustable-rate mortgages?: A fixed-rate mortgage has the same interest rate for the entire loan term, while an adjustable-rate mortgage (ARM) has an initial fixed rate that changes after a set period. Fixed-rate mortgages are generally more predictable.
Can I pay extra toward my mortgage?: Yes, paying extra principal can reduce your loan balance faster and save you money on interest. Many lenders allow bi-weekly payments or extra principal payments without penalty.
What happens if I can't make my mortgage payments?: If you fall behind on payments, your lender may offer loan modifications, forbearance, or foreclosure. It's important to communicate with your lender if you're having financial difficulties.