Personal · Auto · Consumer loans
The real cost of your loan
See your monthly payment, total interest and full payout schedule before you sign. Compare repayment methods and see exactly what an extra payment saves.
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Monthly payment
Repayment method comparison
Extra-payment savings
Amortization schedule
| # | Payment | Principal | Interest | Ending balance |
|---|
Know before you sign
Two ways to repay, very different interest
Equal-payment loans keep your bill steady but front-load interest. Equal-principal loans start higher and shrink to almost nothing. The right pick depends on your cash flow — and an extra payment can cut years off either.
- Amount, rate, term set the baseline.
- Pick a method and watch the interest change.
- Add an extra payment to see months drop off.
- Export the CSV to keep your own record.
Your numbers, laid out honestly
This calculator is for anyone who wants to see exactly where their monthly payment goes—principal versus interest—before signing a loan or refinancing an existing one. Enter your loan amount, annual rate, and term, then compare equal payment against equal principal schedules side by side. If you are considering adding extra monthly payments or a one-time lump sum, the tool shows the revised payoff date and total interest saved. Export the full amortization schedule as CSV to keep for your records or share with a financial advisor.
Loan questions
How is a loan monthly payment calculated?
With the amortization formula: payment = amount × monthly rate ÷ (1 − (1 + monthly rate)^−months). Interest is charged on the remaining balance, so each payment covers that month's interest plus a principal slice.
Equal payment vs equal principal — what's the difference?
Equal payment keeps every monthly bill the same (easier budgeting, more total interest). Equal principal repays an identical chunk of principal monthly, so payments start high and shrink — costing less interest overall.
Does an extra payment actually lower interest?
Yes. Extra principal shrinks the balance, and less balance means less interest on every future month. Even a modest extra $50–100 a month typically shortens the loan by months and saves hundreds to thousands in interest.
Can I pay off a loan early without penalty?
Many personal loans are open to prepayment penalty-free, but some lenders or auto loans charge prepayment penalties. Check your agreement — our calculator models the benefit; only your lender can confirm the cost.