Loan payment calculator
This loan payment calculator gives the monthly payment on any fixed-rate loan, and the sections below explain how it differs from interest-only and balloon payments.
Amortization schedule
| Year | Principal | Interest | Balance |
|---|---|---|---|
| 1 | $3,945.40 | $1,378.64 | $14,054.60 |
| 2 | $4,294.14 | $1,029.90 | $9,760.46 |
| 3 | $4,673.70 | $650.34 | $5,086.76 |
| 4 | $5,086.76 | $237.24 | $0.00 |
Three ways a loan payment can work
A fully amortizing payment, which this calculator computes, repays interest and principal so the balance reaches zero. An interest-only payment covers just the interest, so the balance does not fall. A balloon loan sets a low payment and leaves a large lump sum due at the end. They suit different borrowers, and the fully amortizing loan is the safest to plan around.
If you want to test the other two, the interest-only loan calculator and the balloon loan calculator on this site model them.
Choose a payment you can sustain
Pick the payment first, then check what it buys. The table at the bottom works backward from monthly payments of $200 to $500 to the loan size each one supports at your rate and term. That is the most reliable way to avoid borrowing more than your budget can carry.
$18,000 at 8.5% by loan length
Borrowing $18,000 at 8.5% over 4 years costs $443.67 a month and $3,296 in interest, $21,296 in total. Shorter terms raise the payment but cut the interest, and longer terms do the reverse. The table shows the trade-off across common terms.
| Term | Monthly payment | Total interest | Total paid |
|---|---|---|---|
| 12-month | $1,569.96 | $839 | $18,839 |
| 2-year | $818.20 | $1,637 | $19,637 |
| 3-year | $568.22 | $2,456 | $20,456 |
| 4-year | $443.67 | $3,296 | $21,296 |
| 5-year | $369.30 | $4,158 | $22,158 |
| 7-year | $285.06 | $5,945 | $23,945 |
| 10-year | $223.17 | $8,781 | $26,781 |
How your rate changes the cost
Personal loan rates vary widely with credit score, from the mid single digits for strong borrowers to 30% or more for weak credit. On $18,000 over 4 years, moving from 8.5% to 11.5% adds $1,245 in interest.
| APR | Monthly payment | Total interest |
|---|---|---|
| 5.5% | $418.62 | $2,094 |
| 7% | $431.03 | $2,690 |
| 8.5% | $443.67 | $3,296 |
| 10% | $456.53 | $3,913 |
| 11.5% | $469.60 | $4,541 |
How much can you borrow for a given payment?
Working backwards at 8.5% over 4 years, here is the loan size each monthly payment supports.
| Monthly payment | Loan amount |
|---|---|
| $200/month | $8,114 |
| $300/month | $12,171 |
| $400/month | $16,228 |
| $500/month | $20,285 |
When is half of a $18,000 loan repaid?
With a $443.67 payment, the balance falls below half ($9,000) after 27 payments, about 2.3 years into a 4 years loan. Because interest is highest at the start, the second half of the loan is paid down much faster than the first.
| After | Balance left | Paid so far |
|---|---|---|
| 1 year | $14,055 | $5,324 |
| 2 years | $9,760 | $10,648 |
| 3 years | $5,087 | $15,972 |
Frequently asked questions
What does a loan payment include?
Interest for the month plus a portion of the principal. For secured loans, insurance and taxes are separate costs.
Can the payment change during the loan?
On a fixed-rate loan it stays the same. On a variable-rate loan it can change when the rate resets.
How is a loan payment calculated?
The payment is principal × r ÷ (1 − (1 + r)^−n), where r is the monthly rate (APR ÷ 12) and n is the number of months. Each payment covers that month’s interest first, and the rest reduces the balance.
What is the difference between interest rate and APR?
The interest rate is the cost of borrowing the money. APR also includes certain fees, so it is the better number for comparing offers. This calculator treats the rate you enter as the rate that accrues on the balance.
Related calculators
Estimates from standard loan formulas, not a loan offer or financial advice. Example rates are assumptions: use your own quote.