How the Mortgage Payment Calculator works
Estimate monthly, biweekly and weekly mortgage payments. Adjust the inputs above, then use the calculate button to generate a fresh estimate based on the numbers you entered.
The result is designed to give you a quick planning number, plus a short breakdown of the major figures behind it. You can reset the form at any time and try a different scenario.
When to use this calculator
Use this mortgage payment calculator when you already know the mortgage amount and want to compare monthly, biweekly and weekly payment estimates. It is useful for budgeting before buying, reviewing a renewal offer, or seeing how the same mortgage looks under different payment frequencies.
Formula
Payment = P x r(1 + r)^n / ((1 + r)^n - 1)
- P is the mortgage amount.
- r is the monthly interest rate.
- n is the number of monthly payments in the amortization.
Worked example
For a $400,000 mortgage at 5% over 25 years, the calculator estimates the monthly payment and converts it into biweekly and weekly payment equivalents for planning.
Common mistakes
- Comparing payment frequencies without checking whether they are regular or accelerated.
- Forgetting that taxes, insurance and condo fees are separate from the mortgage payment.
- Using the interest rate from a quote without checking whether it is fixed, variable or promotional.
FAQs
Is biweekly always cheaper?
Regular biweekly payments are usually just a timing conversion. Accelerated biweekly payments can reduce interest because you pay extra over the year.
Does this include mortgage insurance?
No. If mortgage insurance is added to the mortgage, include it in the mortgage amount.
Can I use this at renewal?
Yes. Enter the remaining mortgage balance, renewal rate and remaining amortization to estimate the new payment.