Recently we moved houses. And with the house move, came a brand new mortgage. But as a self-employed person with variable income, I find the steady nature of mortgage payments little hard to digest. So I wanted to know what impact it would have on my mortgage if I make arbitrary extra payments. Unfortunately, I couldn’t find such a calculator. So I made a mortgage calculator with extra payments using Excel. Here is a quick demo of the calculator. Read on if you want to know more or download this.
Mortgage Calculator - DEMO

Download the Mortgage Calculator
Click here to download the Excel Mortgage Payments Calculator (updated with money saved calculation)
How to use this Calculator?
Refer to below illustration and click on the hot spots to understand the process. Essentially, there are 5 things you need to specify or look at when using the template.
- Enter your loan amount
- Enter the loan term (in years)
- Enter the interest rate (APR)
- Specify extra payments in the green column at relevant month rows.
- Look at the chart to understand the impact of your extra payments on the mortgage term.
Enter your mortgage details here.
Enter extra payment amount in relevant month rows.
The chart will show the impact!
How to create such a calculator yourself...
This part of the article discusses the process for constructing such a calculator yourself. Read on (or watch the video tutorial) if you are interested.
The key idea is…
Any extra payments you make bring down the outstanding principal of your loan, thus bringing down the “loan term”.
Step 1: Calculate the monthly (or weekly / fortnightly) payment:
Assuming you have the Loan amount, term & APR in three cells E5, E6 & E7, we can use the PMT() function to calculate the periodic payment.
In my case, let’s say loan is $500,000, term is 20 years and APR (Interest rate) is 5.35% per annum.
Then the Monthly payment would be
=PMT(E7/12,E6*12,E5)

Step 2: Set up amortization schedule
As extra payment will bring down the outstanding loan term, we need to set up an amortization table to see the impact clearly.
So, set up a range of 360 months (or longer if you want to cater for longer mortgages). You can use =SEQUENCE(360) to automatically generate all the months.
Related: Read about SEQUENCE and other Dynamic Array functions in Excel.
Your table should look like this:

- Opening Balance is same as loan amount for month=1. For subsequent months, this will same as previous month’s closing balance.
- Effective term is how long it would take you to pay off the mortgage based on the opening balance, and agreed upon monthly payment (calculated in Step 1) and interest rate (Cell E7). We can use NPER function to get the answer here.
=ROUND(NPER($E$7/12,$E$10,$D13),0) will tell us how many months it is rounded. - Principal Paid is the amount of principal paid in each month. We can get this with the PPMT() function. =PPMT($E$7/12,1,E13,D13)
- Extra Payment is the input column where we can type any extra payments.
- Closing Balance is opening balance minus principal paid minus extra payment.
Complete this table with necessary formulas and fill everything down.
Step 3: Your mortgage will end when the “Eff. Term” is 0.
Go ahead and play with the table by typing some values in the “Extra payment” column. You can see the effective term reducing.
We can visualize the impact with a nice chart (requires some extra work) like this:

Do check the download workbook for details on how the chart is setup.
Video Tutorial - I made a mortgage calculator in Excel
Watch below video to understand how I made the mortgage calculator with flexible payments. If you prefer to see it on YouTube, click here.
Looking for an Amortization Schedule instead?
If you want to make a regular amortization schedule with Excel, check out Excel Amortization Schedule template.
More Financial Models with Excel
If you want to learn more about setting up calculators, models or business systems with Excel, check out below tutorials & examples:
Doing Cost Benefit Analysis in Excel – a case study
Using IRR with Data Tables – Modeling Cash-flow Scenarios in Excel
Nest Egg Calculator using Power BI
Sara’s Copy Shop – Break even analysis and what-if modeling in Excel [Videos]
Interactive Mortgage Calculator to know how much you can borrow (with Excel)

















8 Responses to “Top 5 keyboard shortcuts for Excel Charts”
As far as I remember (checked, again, 2 minutes ago) in my "Excel 2013" in order to select various chart elements I need to use the Arrow keys and not the TAB key.
Practically, the TAB key does nothing (within a Chart).
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Michael (Micky) Avidan
Thanks for pointing this out. This is how I remember it too, but when I was recording the video yesterday, only TAB key worked. MS must have changed the keys in Excel 2016. I have edited the post to include both keys.
The key navigation on charts is different in 2016.
TAB cycles through a layer of objects (SHIFT+TAB cycles backwards)
ENTER move down a layer
ESC moves up a layer
So on a column chart with title/legend/data labels if you select the plotarea the TAB will go through Title > Legend > Plotarea.
ENTER at plotarea will then select Vertical axis. Tab will take you through
Horizontal axis > gridlines > Series > Horizontal Axis.
ENTER with series selected will then allow you to TAB through individual data points and data labels.
If you ENTER on datalabels you can TAB through each data label.
ALT + F1 : to create default chart
ALT+E S T = CTRL + ALT + V, T : I find that easier to remember
I second what Michael already said about TAB and arrow keys. I can't help but think if this is related to the "," or ";" as separator. I prefer to use the chart tools - layout- drop down box, anyway.
Got to be F11 for instant charting. Highlight your data , hit F11 and voila! ?
Ctrl+1 is the most important chart shortcut. In fact, it works for any Excel object: whatever is selected, Ctrl+1 opens the task pane or dialog to format that object.
Somewhere along the line, maybe when Excel 2016 came out, the arrow keys stopped working to cycle through the elements of a chart. But what works is holding Ctrl while clicking the arrow keys. I haven't gotten used to the Tab and other keys, but as long as Ctrl+Arrow works, I'm good.
And F4 used to be so helpful when formatting a lot of charts. But since Excel 2007 came out, it has been mostly useless. It used to remember a whole set of changes at once, so I get that the newer modeless dialogs make that impractical. But now it only seems to work with formatting of lines and borders, and maybe fills. I find myself writing a lot of VBA one-liners in the Immediate Window to handle these tedious formatting tasks.
after clicking on a chart, is there a shortcut key to copy it?
Thank you for the Alt E S T - tip. This is more than a time saver. Because of dynamic charts or de-activated external references to data when you make the charts, you often have empty charts that are otherwise impossible to format. So this shortcut helps adressing that. I will work with it more and see if there remain some obstacles.