About the Mortgage Calculator
Estimate your real monthly mortgage payment — principal and interest plus property tax and insurance — along with the total interest you'll pay over the life of the loan.
Loan figures are among the most personal numbers you will type into a website. Here they stay in your browser — no upload, no account, and no broker calling you afterwards.
Results are estimates for general information only and are not financial advice. Actual loan terms, returns, and taxes vary — confirm figures with your lender or advisor.
How to use it
- Enter the loan amount, or the purchase price minus your deposit.
- Enter the annual interest rate and the term in years.
- Read the monthly payment, the total repaid and the total interest.
What this figure includes — and what it doesn't
The result is principal and interest only. Your actual monthly outgoing will also include property tax, homeowners insurance and, below a 20% deposit, mortgage insurance (PMI).
Those extras routinely add 20–30% on top of the principal-and-interest figure, which is why a payment that looks affordable in a calculator can feel very different in practice.
A worked example
A $320,000 loan at 6.65% over 30 years:
- Monthly principal and interest: $2,054.29
- Total repaid over the term: $739,544
- Of which interest: $419,544
You repay more in interest than you borrowed. That is not unusual at 30 years — it is what the term costs. Cut the same loan to 20 years and the monthly payment rises to about $2,414, but total interest falls to roughly $259,000.
Common mistakes
- Budgeting on the principal-and-interest figure alone and being surprised by escrow.
- Comparing quotes on the monthly payment rather than the rate and term together — a longer term always lowers the payment and raises the cost.
- Forgetting closing costs, which typically run 2–5% of the loan amount and are due upfront.
Questions people ask
How much difference does the rate really make?
On a $320,000 30-year loan, each quarter-point is roughly $50 a month and around $18,000 over the full term. It is worth shopping around.
Should I take a 15-year mortgage?
It costs far less in total interest but demands a much higher monthly payment. The right answer depends on whether that payment leaves you room for emergencies.
Does paying extra each month help?
Substantially, because extra payments go straight against the principal. Even $100 a month on this example removes several years from the term.