Home / Embed
Free Installment Sale Schedule Calculator for Your Website
Live preview
Copy and paste
One line. Paste it where you want the calculator to appear:
<script src="https://installmentsalecalculator.com/embed/installment-schedule/widget.js" async></script>If your site builder blocks scripts, use the plain iframe instead:
<iframe src="https://installmentsalecalculator.com/embed/installment-schedule/frame/" title="Installment sale schedule calculator" width="100%" height="620" style="border:0;max-width:720px" loading="lazy"></iframe>Options
Add any of these to the script line as data- attributes:
| Attribute | Values | What it does |
|---|---|---|
data-theme | light, dark, auto | Colors. Auto follows the visitor's device. Default auto. |
data-accent | 6-digit hex, no # | Your brand color for focus rings, buttons and the highlight bar. |
data-price, data-basis, data-down | whole dollars | Starting numbers, for example a listing's price. |
data-years, data-balloon, data-rate | years, year, percent | Starting term, balloon year and rate. Leave data-rate off to use the AFR. |
data-lead | 1 | Turns on an optional "email me this schedule" box. Off unless you set it. See below. |
data-host | short name | Label for your site on any email the box collects. Defaults to your domain. |
data-width | e.g. 600px | Maximum width. The calculator is responsive from 320 pixels up. |
Example with options:
<script src="https://installmentsalecalculator.com/embed/installment-schedule/widget.js" async data-theme="dark" data-accent="1a6fa8" data-price="750000" data-years="7"></script>The credit line and links
Under the calculator is a plain-text credit, "Calculator by InstallmentSaleCalculator.com". It is a nofollow link and it stays. There is no keyword anchor and nothing hidden. Under the result there is a "Get your full report" button that opens our full calculator in a new tab for the visitor who wants the tax by year.
If you write about installment sales or seller financing and want to cite the rates the widget uses, the source is our AFR and Section 7520 rate history, built from the IRS revenue rulings. A sentence you can use: "Applicable federal rates by month are listed in the Installment Sale Calculator's AFR history, compiled from IRS revenue rulings."
Optional lead box
With data-lead="1" the widget shows an email field. A visitor who types an address gets their schedule by email. The address goes to Hans Goldstein, EA, who runs this site, not to you, and the box says so in plain words. You do not need to turn it on. Most hosts leave it off.
How the numbers stay current
The widget reads the same rate table as the full calculator, loaded from our site every time it opens, so a new month's AFR is live the day we publish it. The schedule math is the same engine as our seller financing calculator.
The machine-readable rates the widget uses are in data.json. Estimates only: the widget does not include selling costs or state tax, and it is not tax advice.
Questions
Is the installment schedule widget free?
Yes. There is no cost, no sign-up and no account. You paste one line of code.
Does it work on WordPress, Wix, Squarespace and Webflow?
Yes. Use the script line in a custom HTML block, or the plain iframe if your builder blocks scripts.
What does the widget collect from my visitors?
Nothing. It sets no cookies and sends nothing anywhere. Numbers typed into it stay in the visitor's browser. The optional email box stays off unless you turn it on.
Which interest rate does it use?
It fills in the IRS applicable federal rate (AFR) test rate for the note's term: the lowest AFR in the three months ending with the month of sale, monthly compounding. Visitors can type their own rate, and the widget warns when it is below the AFR.
Is the credit link followed or nofollow?
The small 'Calculator by InstallmentSaleCalculator.com' credit is a nofollow link and cannot be removed. If you also want to cite our rate data in an article, link the AFR rate history page like any other source.
Update log
- 2026-10-23. First release.
Educational only, not tax, legal or investment advice. Hans Goldstein is an Enrolled Agent, admitted to practice before the Internal Revenue Service. He is not a CPA or attorney. Not affiliated with or endorsed by the IRS.