Loan Calculator

How this result is built

Calculate the payment, interest, and schedule for a fixed-rate loan with optional extra principal.

A fixed loan payment is set so the balance reaches zero at the last period. Raise the rate or the term and you change both the payment and the interest, in opposite directions more often than not. A longer term is the usual way a payment gets smaller and the interest gets larger.

What the opening example is for

Extra principal is optional. At zero, the schedule matches the original term. Above zero, the loan ends early and the interest line falls.

The walkthrough below uses the numbers already sitting in Loan Calculator. Press Calculate and the headline should match this page. Then put your own figures in. The math does not run until you press the button, and Clear hides the result.

What each field is doing

The “Loan amount” line on Loan Calculator starts at $15,000.00. Leave that figure only when it matches the statement, the quote, or the plan you are testing. Press Calculate after the edit so the chart and the schedule move with it.

Loan Calculator treats “Interest rate” as its own entry, and the form opens with 9.50%. A round example is useful for learning the page. It is a poor substitute for the number on your own paperwork, so replace it and run the form again.

The remaining fields

Before you replace it, “Term” reads 4 on Loan Calculator. The other fields stay put while you change this one. That is the clean way to see what this line is doing inside the result.

Look at “Extra principal each month” first if you are checking Loan Calculator: the filled value is $0.00. If the label is a rate, type the annual figure the contract uses. If it is money, type the amount that will actually move, not a rounded hope.

The opening result, line by line

Press Calculate on the opening form and Monthly payment is $376.85. That is the number the rest of this section is talking about.

Amount financed is $15,000.00 when you run the opening figures on Loan Calculator. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

On this opening pass, base payment is $376.85. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

Loan Calculator reports that total interest is $3,088.65. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

How those lines were produced

Total paid is $18,088.65 when you run the opening figures on Loan Calculator. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

On this opening pass, payoff time is 4 years. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

A second pass changes only “Loan amount”, from $15,000.00 to $16,500.00. Monthly payment moves from $376.85 to $414.53. Nothing else on the form was edited, so the gap between those two results is the effect of that one field on Loan Calculator. If the gap is tiny, this page is not very sensitive to that entry. If the gap is large, get that entry from a document before you plan around the result.

What this page will not claim

Loan Calculator applies the balance, the rate, and the payment you type. A lender’s payoff letter can include a fee or a daily interest convention this form does not see. Use the letter when you are sending the final check.

Loan Calculator stops at its own formula. When the next question is different, open Payment Calculator (The payment that links a balance to a future value.); Amortization Calculator (A schedule that shows where each payment goes.); Personal Loan Calculator (Note amount, fee, payment, and APR.). Do not add those results to this one as if they were the same kind of dollar.

Check the result before you use it

Start on Loan Calculator by reading the labels, not the headline. The opening labels are Loan amount ($15,000.00), Interest rate (9.50%), Term (4), Extra principal each month ($0.00). If a label is not the fact you have, the result cannot turn into that fact later. The illustration on the form lands on $376.85. When you press Calculate and see that same figure, the button and this explanation are using one formula.

Change one field at a time. Write down the headline, edit a single line, and press Calculate again. A large jump means that line carries the result. A line that does not move is a line the formula ignores, which is a reason to confirm you opened the right page. Loan Calculator is built for one job: A fixed payment, a rate, and the interest it creates. The description on the page says the same thing in a sentence: Calculate the payment, interest, and schedule for a fixed-rate loan with optional extra principal.

When the paperwork disagrees

Then hold the headline next to a source outside the site. That source might be a loan estimate, an account statement, a pay stub, or the public limit named in the methodology. A few cents of difference on a long schedule is ordinary rounding. A different rate, a fee you never typed, or a tax the form does not ask for is not rounding. Correct the input. Do not average the page with the paperwork.

When the outside source still disagrees, Loan Calculator has reached the edge of what it will claim. It will not phone a lender, pull a county record, or apply a credit you left blank. Send the calculator name, every input, and the result you expected through the contact page if you think the formula itself is wrong. Until that is settled, read $376.85 as the output of the fields above and nothing else.

FAQs