See how extra payments can shorten mortgage life and reduce total interest.
Overview
Extra principal is one of the strongest tools for reducing mortgage interest cost.
This calculator compares standard payoff versus accelerated payoff paths.
Even modest recurring extras can move payoff date materially forward.
Use realistic, sustainable extra amounts to avoid cash-flow strain.
Steps
Use latest outstanding principal.
Input remaining APR and months.
Set recurring or one-time principal addition.
Compare old and new payoff timelines.
Assess cumulative reduction in lifetime interest.
Math
New Balance_t = Old Balance_t - Extra Principal_t
Additional principal directly lowers future interest base and accelerates balance reduction.
Worked cases
Apply extra principal each month to revised schedule.
Payoff timeline shortens with meaningful interest savings.
Apply annual principal reduction and compare schedule.
Periodic lump sums can rival monthly extras in impact.
Combine recurring and lump-sum reductions.
Hybrid plans often balance consistency and flexibility.
Why use this
Questions