Biweekly Mortgage Calculator — Pay Off Your Home Faster
Switching from monthly to biweekly mortgage payments squeezes in one extra full payment per year, slicing years off your loan and saving thousands in interest — with no change to your budget.
$
%
years
Pay this amount every two weeks instead of monthly
- 1
Monthly interest rate
r = 6.5% ÷ 12 ÷ 100 = 0.005417 - 2
Number of payments
n = 30 × 12 = 360 - 3
Growth factor
(1 + 0.005417)ⁿ = 6.9918 - 4
Monthly payment
300,000 × 0.005417 × 6.9918 ÷ (6.9918 − 1) = 1,896.2 - 5
Biweekly payment
1,896.2 ÷ 2 = 948.10Pay half the monthly amount every two weeks — 26 payments/year equals 13 monthly equivalents.
How does this calculator work?
Biweekly mortgage payments (half your monthly amount, 26 times a year) equal 13 monthly payments annually instead of 12. The extra payment attacks principal directly, typically cutting a 30-year loan by 4-5 years and saving tens of thousands in interest with no change to your standard payment size.
Formula
How this is calculated
A standard mortgage payment is made once a month — 12 times a year. A biweekly plan splits each payment in half and makes it every two weeks, which produces 26 half-payments (13 full monthly equivalents) per year. That one extra payment is applied entirely to the principal, reducing the balance faster and shrinking every future interest charge.
This calculator derives the standard monthly payment using the amortisation formula M = P · r_m · (1+r_m)^n / ((1+r_m)^n − 1), sets the biweekly payment to M/2, then simulates the paydown period by period using a biweekly interest rate of annual_rate/26. The balance chart shows the accelerated payoff curve.
The results assume payments are applied immediately and that the lender supports a true biweekly plan (where each payment reduces the balance on the same day, not held until month-end). Some lenders hold the first payment and apply both together at month-end — which reduces the benefit to near zero. Always confirm with your lender that your plan is a true biweekly schedule.
Frequently asked questions
On a $300,000 loan at 6.5% for 30 years the standard monthly plan costs roughly $382,000 in total interest; the biweekly plan cuts it to about $311,000 — around $71,000 saved — and shaves roughly 4-5 years off the term.
Not all lenders have an automatic biweekly programme, and some charge a fee to enrol. An equivalent DIY approach: make your normal monthly payments and add 1/12 of a monthly payment as extra principal each month. The math is identical.
If you are using the DIY "extra 1/12" approach you can stop the extra payment at any time. If you are on a formal biweekly plan through your lender, check the terms — some lock you in or charge an exit fee.
TG we-Calculate Editorial Team. (2026). Biweekly Mortgage Calculator — Pay Off Your Home Faster [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/biweekly-mortgage-calculator
TG we-Calculate Editorial Team. "Biweekly Mortgage Calculator — Pay Off Your Home Faster." TG we-Calculate. 2026. https://we-calculate.com/calculator/biweekly-mortgage-calculator.
TG we-Calculate Editorial Team, "Biweekly Mortgage Calculator — Pay Off Your Home Faster," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/biweekly-mortgage-calculator
@misc{wecalculate_biweekly_mortgage_calculator, title = {Biweekly Mortgage Calculator — Pay Off Your Home Faster}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/biweekly-mortgage-calculator}}, year = {2026}, note = {TG we-Calculate} }
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