PayoffMath calculators
Start with the question, not the loan type. When is this paid off? What does extra cash save, and when does it save the most? Does this refinance actually recover its closing costs? Which debt should go first if you have several? What is the true APR after the origination fee? What home price fits your income? What does a business credit line actually cost? Pick the calculator that matches your question. The loan-type lists below run the same math with each program's specifics — FHA MIP, HELOC draw periods, SBA fees — built in.
Strategy comparison
Debt Payoff Strategy Calculator →
Have multiple debts? Enter them all and compare avalanche vs. snowball vs. equal split side-by-side. Most calculators show one method at a time — this one shows what each costs, so you know exactly what you're giving up if you pick the motivational option over the cheapest one.
Allocation framing
Invest vs. Prepay Calculator →
Got extra cash flow? Compare paying down a 6% loan vs. investing the same money at 8%. Side-by-side net worth chart, the crossover month where one path overtakes the other, and the exact return rate you'd need to break even.
Refi math
Refinance Break-Even Calculator →
How long until refi savings cover closing costs? See break-even months AND lifetime interest savings net of closing — so the term-extension trap can't hide behind a flashy “$200/month savings” pitch.
Honest cost
Effective APR Calculator →
What's the real APR after the origination fee, prepayment penalty, and tax deduction? Three lenses on the same loan stacked side-by-side so the chain of adjustments is legible instead of buried in a single number.
Servicer reality
Biweekly Payment Calculator →
Half the monthly amount every 2 weeks adds up to one extra payment a year — if your servicer applies partial payments to principal. Most don't. Compares true biweekly, the DIY workaround, and a vendor-fee program side-by-side.
Mortgage qualification
Debt-to-Income Calculator →
Enter your monthly income and debts. See your front-end and back-end DTI ratio plus which lender band you're in. Plus how much room you have before crossing the 36% safe threshold that drives most mortgage approvals.
How much house?
Home Affordability Calculator →
Enter your income, debts, down payment, and mortgage rate. See the max home price that fits standard lender DTI caps — plus the full PITI breakdown and which constraint is capping your number.
Borrower's view
Business Overdraft Cost Calculator →
What you'll actually pay on a business overdraft — interest on the drawn balance, every fee that hits, and the effective APR. Plus a full-draw comparison so you can see whether the unused line is earning its keep.
Lender's view
Business Overdraft Income Calculator →
The same facility from the bank's side — interest, commitment fee, spread, and yield on the limit at any draw level. Useful when you want to understand the economics behind the rate quote you're being shown.
Three-option compare
Overdraft vs Term Loan vs Credit Card →
You need money for a few days, weeks, or months. Three options are usually on the table. Side-by-side cost ranking with a sensitivity table that shows the holding period at which the cheapest option flips.
Home loans
Mortgages, refinancing, home equity products. Same math, different programs and rules.
Mortgage →
Use it for a 15-year mortgage payoff plan, or compare the same extra-payment strategy against a 30-year — see when the mortgage actually disappears and what extras buy you.
Home equity loan →
Enter your balance, fixed rate, monthly payment, and any extra you can add — see a planning estimate of your payoff date, total interest, and how much extra principal would save. Fixed home equity loan only (not a HELOC).
HELOC →
Enter your HELOC balance, rate, monthly payment, and any extra you can add — see a planning estimate of payoff time, interest, and how extra principal changes the math.
Refinance →
Enter the proposed new rate, term, and balance — estimate the new monthly payment, total interest, and the break-even month after closing costs. A lower payment is not the same as a lower total cost.
VA loan →
Veterans, active-duty, surviving spouses — VA loan payoff math, with the funding-fee and no-PMI quirks the standard mortgage calc doesn't model.
FHA loan →
FHA loans — first-time buyers' workhorse, but the MIP math is what makes payoff strategy different from conventional.
USDA loan →
USDA Rural Development loans — zero-down for eligible rural buyers, with two fees the calculator math hides.
Consumer loans
Personal, auto, and student loans. Anything secured against income rather than property.
Personal loan →
The pillar calculator — typical $20k consumer-credit personal loan, fixed rate.
Auto extras →
Type your loan numbers and an extra-monthly amount — see how many months it shaves off, how much interest you keep, and where the timing matters more than the size.
Auto loan →
Enter your balance, APR, monthly payment, and any extra you can add. See the payoff date, total interest, and how much sooner principal-only extras get you to title-in-hand.
Auto refinance →
Plug in the proposed refi terms — see the new payment, total interest, and whether the lower rate actually beats just keeping your current loan.
Student loan →
Enter balance, rate, required payment, and any extra you can add. See your payoff date and total interest — then check whether you're on a payoff track or a program track.
Business loans
SBA-backed and non-SBA business financing.
SBA loan →
Plan an SBA 7(a) or 504 payoff before a sale, refinance, or closing date. The calculator gives an amortization estimate — the lender's payoff quote, penalty window, and release documents control the final number.
Small business loan →
Term loans, lines of credit, online business lenders — same math, different prepayment rules.