Fixed Principal Payment Loan Calculator

Includes a printable amortization schedule and charts.

What is a fixed principal loan?

Fixed Principal Loan Calculator
Fixed Principal Loan Calculator

Fixed Principal Payment Loan

  • A loan characterized by a declining payment.
  • Amount allocated to principal is the same for each payment.
  • Less total interest than "normal," level payment loans.

A fixed principal loan is a loan where the borrower repays a fixed amount of the principal loan amount each period until they have fully paid off the loan. The interest on the loan is calculated based on the unpaid principal balance, which decreases over time as the borrower makes principal payments. A declining periodic payment due to a decreasing interest amount is one of the characteristics of a fixed principal loan.

In contrast, a traditional loan has fixed (sometimes called "level") periodic payments comprised of increasing principal and declining interest. The principal amount paid each period increases (to keep the same payment) because the interest amount decreases due to the declining principal balance.

Why are fixed principal loans advantageous to borrowers?

Fix principal payment loans reduce the interest amount paid because the borrower pays the principal loan amount off faster than they would if they had a traditional loan.

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Instructions for the fixed principal calculator

Enter the four primary inputs:

  • Loan Amount: Enter the total amount of the loan you wish to take out. This should be entered as a positive number.
  • Number of Payments: Enter the total number of payments you will make to pay off the loan. This should be entered as a positive whole number.
  • Annual Interest Rate: Enter the annual interest rate for the loan, expressed as a percentage. For example, if the annual interest rate is 5%, you would enter "5" for this field.
  • Payment Amount: Enter the amount of each payment you will make to pay off the loan. This should be entered as a positive number.

These secondary inputs must all be set. If you are not sure about any of them, we suggest that you leave them set to their default setting.

  • Payment Frequency: Select the frequency of payments you will make to pay off the loan. This can be monthly, bi-weekly, weekly, or other intervals.
  • Compounding: Select the compounding frequency of the loan. This is the frequency at which the interest is calculated and added to the loan balance. If the loan documents do not specify a compounding frequency or you don't know it, then set it to be the same as the payment frequency.
  • Payment Method: Select the payment method you will use to pay off the loan. If the first payment is due when the loan originates set this option to "Advance." Otherwise, we'll assume the first payment is due one period after the origination date (when the funds are available) and in that case, this must be set to "Arrears."

23 Comments on “Fixed Principal Payment Calculator”

Join the conversation. Tell me what you think.
  • Where can I get an amortization schedule for an interest free personal loan with a fixed monthly payment?

    • You can use this amortization calculator.

      Normally, setting one of the 4 main inputs (loan amount, number of payments, interest rate or payment amount) to zero causes the calculator to solve for that input.

      In your case, since there’s no interest, the interest rate is 0.0%, and you’ll not want the calculator to solve for a rate.

      Therefore, look at the "amortization method" and select "No Interest".(Then you can enter zero for the interest rate.)

      Hope this helps.

  • Greg Brown says:

    A start date would be useful. Also, for daily compounding, monthly interest would not be annual interest / 12, but either 30 or 31 days of daily interest, depending on the month (28 for Feb, of course). Thanks.

  • If I borrow $16,200 by signing a 3-year, 6% note payable and the note payable is repayable in three annual fixed principal payments is my compound monthly or yearly ?

    • It could be either or neither. The compounding depends on the term of the loan. When in doubt, though, set the compounding equal to the scheduled payment frequency.

  • Also, how can I calculate that with blended principal payments ?

    • Sorry, I don’t understand this question. How do you calculate what?

      • I curious how to calculate the fixed principle payment, how can i make the formular myself when using excel

        • I don’t discuss formulas or equations. If I get into that, there would be no time left to work on this site (I only do this part-time). But, the fixed principal portion is the total principal divided by the number of payments. Then you add the accrued interest. It is probably the simplest of all payment calculations.

  • In determining the annual interest payments for a 4-year Note with annual fixed principal payments and 2% annual compounding, it appears the interest payment each year is just 2% * outstanding principal. Is this correct? I was thinking it should be 2% * (outstanding principal + previous year’s interest). Thank you.

    • Assuming that the annual payment including the interest due was paid on time, it is correct that the interest is on the outstanding balance only.

  • Hi..
    First of all, thank you for the effort you put into making those calculators.
    I used the “Fixed Principal Payment Calculator” and I got results different from that when I used “Loan Calculator with options”. My goal was to use the “Loan Calculator with options” in order to use the “Extra payments” feature, but before doing so I wanted to make sure that this calculator would give the same results as the “Fixed Principal Payment Calculator”, which was not the case.
    – Loan amount = RMB 1,080,000
    – Number of payments = 216
    – Annual Interest Rate = 5.25%
    – Payment Frequency & Compounding = Monthly
    – Payment Method = Arrears (Loan)

    When using “Fixed Principal Payment Calculator”, I get 1st payment=RMB 9725, and the Total Interest= RMB ¥512,663.04 which are the correct numbers, but when using the “Loan Calculator with options” results are different.
    Am I missing something?
    Thanks for your help in advance.

    • Hello, I get exactly the same result with both calculators, and my result matches your results. That’s assuming by loan calculator with options, you mean this calculator.

      Did you change any of the dates with the loan calculator? If so, that will change the results. How do you have your interest options set? What are the dates you used, assuming the loan date and first payment date are not exactly one month apart. If the dates are not a month apart, set them so they are, then you’ll see the results match. The loan calculator is accurate enough that if you change the dates, the results change.

      • Hello Karl, thank you for your kind reply.
        your reference to the loan calculator with options is correct.

        I just tried it again and it’s ok now. I think I know what my mistake was. I should have set “payment amount” to zero BEFORE pressing “calc”.

        Thank you once again..

  • The changes to this website have really dragged down the functionality. I can no longer run an amortization schedule and bump in extra payments to that schedule. I don’t see where I can do this among the breakout of calculators. I am unable to input any mortgage terms for some of the calculators to even run them so I no longer find this website useful. It’s a shame that when something works as the original website had, someone feels duty bound to tweak into dysfunctional oblivion.

    • I’m sorry you are having problems with the updated site. However, there should be no issues. You should be able to do what you did on the prior site.

      However, you didn’t give me any specifics, so it’s hard for me to say why you are experiencing problems.

      I will point out that it is possible that setting from prior visits are being carried over in your case from the old site. This should not happen. If you experience a problem with a calculator page, please do a hard refresh (see additional note at the end of this comment).

      Please let me know specifics if you have an issue after a HARD refresh of the page.

      (Sites have to change, otherwise, browser technology changes and sites will eventually stop working. With the last update, I tried to get ahead of the curve.)

      Hard reset:

      If you do not see the change right away, you may have to perform a hard refresh of the page:

      Depending on your operating system all you need to do is the following key combination:

      • Windows: ctrl + F5
      • Mac/Apple: Apple + R or command + R
      • Linux: F5

      Above, from Refresh Your Cache.

    • As far as creating an amortization schedule with extra payments, is this the calculator you are looking for:

      Extra Payment Calculator

      The calculators themselves did not change between the old site and the new site. You can get to any of the calculators you were using on the old site on this new site by changing to followed by the same calculator.

  • how can i copy the schedule to an excel sheet?

    • The ability to select and copy a schedule is only available to subscribers.

      Also, so you know, copying and pasting to a spreadsheet can be a hit or miss feature, depending on the operating system, browser and spreadsheet, results vary.

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