Nitro ToolzExtra Mortgage Payment Calculator
Interest and time saved by paying extra principal.
Extra Mortgage Payment Calculator
Generated 10/9/2026
- Current loan balance: 280000
- Interest rate: 6.5
- Years remaining: 27
- Extra principal per month: 250
- One-time extra payment: 0
- Time saved
- 6 yr 11 mo
- Interest saved
- $93,175
- New payoff time
- 20 yr 1 mo
- Original payoff time
- 27 yr
- Regular monthly payment
- $1,835.55
- Payment with extra
- $2,085.55
- Total interest with extra
- $221,544
Chart loads when visible.
How to use this tool
- Enter your balance, rate and years left.
- Add a monthly extra amount, a one-time lump sum, or both.
- Check time and interest saved, then compare the two balance lines.
Formulas
Each month: interest = balance x r; principal = payment + extra - interest; balance falls by principal.
Savings = original total interest - total interest with extra payments.
Frequently asked questions
Do extra payments reduce the term or the payment?
Typically the term, if you tell your servicer to apply the extra to principal. This tool models a shorter term.
Is paying extra better than investing?
It depends on your mortgage rate versus expected after-tax returns, and how you value a guaranteed result. Paying down debt is a certain return equal to your rate.
Are there prepayment penalties?
Most modern mortgages have none, but check your note. Some loans restrict large lump sums.
Does it work at 0%?
Yes. Extra payments still shorten the term, though there is no interest to save.