Loan Calculator
Calculate your monthly payment, total interest, and full amortization schedule.
Pay the loan down with a fixed amount every period - the usual setup for a personal, auto, or student loan.
Applied straight to principal - shortens the payoff time and cuts total interest
A single lump sum, applied straight to principal in the month below
Set an amount above first
Monthly payment
Payoff in 5 yr, around September 2031.
Amortization schedule
| Year | Principal Paid | Interest Paid | Ending Balance |
|---|---|---|---|
| 1 | $4,281.58 | $1,729.81 | $20,718.42 |
| 2 | $4,613.97 | $1,397.42 | $16,104.46 |
| 3 | $4,972.16 | $1,039.22 | $11,132.29 |
| 4 | $5,358.16 | $653.22 | $5,774.13 |
| 5 | $5,774.13 | $237.25 | $0 |
All displayed values are estimates only, for illustrative and informational purposes, not a loan offer or financial advice - actual rates and terms depend on your lender.
This calculator provides general estimates for informational purposes only and is not financial, investment, or tax advice - verify the figures and consult a qualified professional before making financial decisions.
Results are provided "as is" and may contain errors or inaccuracies - please verify them before relying on them, and use this tool at your own risk.
How it works
Every fixed-rate loan payment is split between interest (charged on whatever balance is still outstanding) and principal (which reduces that balance) - early on, most of the payment is interest, since the balance is still high; later, most of it is principal, since the balance has shrunk. This tool computes the standard fixed monthly payment formula, then simulates the loan month by month to build the full schedule. Any extra monthly payment you add goes straight to principal, which is why it shortens the loan and reduces total interest by more than the extra amount itself.
Read the full guideHow to use it
- Pick a loan type - fixed payments, a lump sum due at the end, or working backward from a target amount - then enter the amount, interest rate (APR), start date, and term.
- For fixed payments, optionally add a recurring or one-time extra payment, or switch to bi-weekly payments, to see how much sooner the loan would be paid off and how much interest you'd save.
- Review the monthly payment, total interest, and total paid, or scroll the year-by-year schedule below and download it as a CSV.
Examples
Frequently asked
- Why does most of my early payments go to interest?
- Interest is charged on the current balance, which is highest at the very start of the loan - as the balance drops with each payment, less of the next payment is needed for interest and more goes toward principal. This is normal for any fixed-payment amortizing loan, not something specific to a bad rate.
- How much does an extra payment actually save?
- More than just the extra amount, because it's applied entirely to principal - which means less interest accrues on every remaining month of the loan, not just the one you paid extra on. The tool shows both the interest saved and the time saved side by side.
- What does APR mean here?
- The Annual Percentage Rate - the yearly interest rate used to compute the monthly rate (APR ÷ 12) applied to the outstanding balance each month.
- What's the difference between the three loan types?
- Fixed payments is a normal amortizing loan - you pay the same amount every period until it's paid off. Lump sum at the end defers everything: nothing is paid until maturity, when the balance plus all the interest it accrued comes due at once. Target amount runs that same math backward - tell it what you need at a future date, and it works out the smaller amount today that grows into it, the same relationship a bond's price has to its face value.
- What's the difference between a recurring extra payment and a one-time one?
- A recurring extra payment is added to every single payment, so its effect compounds every period. A one-time payment is a single lump sum - a bonus, a tax refund, an inheritance - applied to principal in whichever month you pick. Both shorten the loan and cut total interest, but a one-time payment's savings depend on how early it lands: the earlier it's made, the more months of interest it avoids.