Add this calculator to your website

One script tag. No plugin to install, no framework required. Works on any site — WordPress, Shopify, Squarespace, Wix, or a plain HTML page.

Live preview — free version

This is the actual widget, running from this page, using the same 2026 rate table as the rest of the site.

Free or Pro

Free

$0
  • All 13 provinces & territories
  • Bidirectional (before-tax, tax, or total)
  • Fits any width — sidebar or full page
  • Small “Powered by” credit link
  • Default colours

Pro

Coming soon / per site / year
  • Everything in Free
  • No credit link
  • Match your brand colour
  • Priority support if rates change
Coming soon — not yet available

Paste this where you want the calculator to appear:

<div data-swg-gst-widget></div>
<script src="https://gsthstcalculator.com/widget/gst-widget.js" async></script>

That's it — no signup, no API key. The widget sizes itself to whatever container you put it in, so the same code works as a full-width block or in a narrow sidebar. It keeps a small “Powered by GST/HST Calculator” link at the bottom, which links back here.

Same code, narrow container

Not for sale yet — this tab shows what the Pro embed code will look like once it launches.

<div data-swg-gst-widget data-license="YOUR-LICENSE-KEY" data-accent="#0a7d3e"></div>
<script src="https://gsthstcalculator.com/widget/gst-widget.js" async></script>

Same snippet, plus a license key and an optional accent colour. No credit link is shown when a license key is present.

Common questions

Will this slow down my site?
The script loads async and is a single small file with no other dependencies — it won't block your page from rendering.
Do I need to update it when tax rates change?
No. The widget always uses the current rate table from this site, so a provincial rate change is reflected automatically — nothing to reinstall.
Does it work on WordPress?
Yes, as an HTML/custom-code block with the same snippet above. A dedicated WordPress plugin isn't built yet.
Is there a WordPress plugin or desktop app?
Not currently — see our about page if you'd like to be notified when Pro or other formats launch.

Rates last checked: September 2026, from the same table used across this site.