How much do extra payments save?

It depends on your rate and balance, but even small extra monthly payments or switching to accelerated bi-weekly can cut years and tens of thousands in interest. This calculator shows the exact savings vs. a plain monthly payment.

Does it handle Canadian mortgages?

Yes — choose Canada and it uses semi-annual compounding (the Canadian standard) and CAD, and adds a CMHC premium when your down payment is under 20%.

What's accelerated bi-weekly?

You pay half your monthly amount every two weeks. Because there are 26 bi-weekly periods, you make the equivalent of 13 monthly payments a year, paying the loan off faster.

Calculators › Home Buyer & Owner › Mortgage Calculator

Calconomics

Mortgage Calculator

Model your mortgage with every knob that matters: payment frequency (including accelerated bi-weekly), extra monthly payments, annual lump sums, and mortgage insurance — with correct US monthly and Canadian semi-annual compounding. See exactly how much interest and time you save.

Region

Country

Property & loan

Home price

Down payment

Interest rate

Amortization

yrs

Payment options (the knobs)

Payment frequency

Extra payment added every month

Annual lump-sum prepayment

Carrying costs

Property tax annual

Home insurance annual

HOA / condo fee monthly

Payment (P&I)

$2,275

per period

Total monthly housing

$2,850

P&I + tax + ins + fees

The numbers

Mortgage amount	$360,000
Mortgage insurance	$0
Payoff time (years)	30
Total interest paid	$459,160
Interest saved vs. plain monthly	$0

US$9.99 · download & own it forever

Prices in

✓ Includes the full toolkit. One purchase — this calculator already does everything these do, no add-ons: Biweekly Mortgage Calculator · Extra Mortgage Payment Calculator · PMI Calculator

How it's calculated

US loans compound monthly; Canadian fixed mortgages compound semi-annually — the payment formula adjusts by country.
Accelerated bi-weekly = half the monthly payment every two weeks (26/yr ≈ 13 monthly payments), shortening amortization.
Under 20% down, Canada adds a CMHC premium to the loan; the US adds monthly PMI.
Interest/time saved is measured against a plain monthly payment with no extras.

Our methodology & 2026 data sources →

Frequently asked questions

How much do extra payments save?: It depends on your rate and balance, but even small extra monthly payments or switching to accelerated bi-weekly can cut years and tens of thousands in interest. This calculator shows the exact savings vs. a plain monthly payment.
Does it handle Canadian mortgages?: Yes — choose Canada and it uses semi-annual compounding (the Canadian standard) and CAD, and adds a CMHC premium when your down payment is under 20%.
What's accelerated bi-weekly?: You pay half your monthly amount every two weeks. Because there are 26 bi-weekly periods, you make the equivalent of 13 monthly payments a year, paying the loan off faster.