Mortgage Calculator
Calculate your monthly mortgage payment, total interest over the loan term, and how much of each payment goes toward principal vs interest.
What Does This Tool Do?
Calculate your monthly mortgage payment using the standard amortisation formula. Shows total amount paid over the loan term, total interest cost, and first-payment principal vs interest split.
Key Features
Monthly Payment
Exact payment using amortisation formula.
Total Cost
Total amount paid and total interest over full term.
Payment Split
First payment principal vs interest breakdown.
Multiple Terms
10, 15, 20, 25 and 30-year terms.
How to Use
- Enter the loan amount.
- Enter the annual interest rate.
- Select the loan term.
- Click Calculate.
Frequently Asked Questions
What is the mortgage payment formula?▾
M = P × r(1+r)^n / ((1+r)^n − 1), where P is principal, r is monthly rate (annual÷12) and n is total months.
Does this include taxes and insurance?▾
No — this calculates principal and interest (P&I) only. Your actual payment may be higher if your lender includes property tax and insurance (PITI).
How does the interest rate affect the payment?▾
A 1% rate increase on a $300,000 30-year mortgage increases the monthly payment by roughly $170 and total interest by about $60,000.
Complete Guide to Mortgage Calculator
When To Use This Tool
Use Mortgage Calculator whenever you need fast, accurate output without installing software. This tool is designed for speed, clarity, and repeatable results for day-to-day work.
Best Practices for Accurate Results
- Double-check the format of your input before running the tool.
- Test with a small sample first, then process larger data.
- Use Related Tools to verify, convert, or transform the output.
Why Users Prefer AdeDX
AdeDX tools are browser-based, free to use, and built to work across desktop and mobile devices. Most processing happens directly in your browser for fast performance and improved privacy.