Put a surcharge calculator
on your website.
Widget
Embed code
<!-- Fuel surcharge calculator by MarginShock --> <iframe data-marginshock src="https://marginshock.fourleafstechnology.com/embed/calculator" title="Fuel surcharge calculator" loading="lazy" style="width:100%;max-width:960px;height:1150px;border:0"></iframe> <p style="font:13px/1.4 system-ui,sans-serif;margin:6px 0 0">Calculator by <a href="https://marginshock.fourleafstechnology.com/fuel-surcharge-calculator?utm_source=embed-link">MarginShock</a></p> <script src="https://marginshock.fourleafstechnology.com/embed.js" async></script>
Paste it into any page that accepts HTML. The small script resizes the widget to fit; without it the widget still works at a fixed height.
Live preview
(Who it’s for)
Useful for anyone whose audience is feeling the costs.
Trade associations
Give members a tool for this year's fuel and cost increases, on your own site.
Fuel card & fleet companies
Help small-fleet customers price the costs you already help them track.
Accountants & bookkeepers
Send clients somewhere useful when they ask how much to raise prices.
Industry blogs & publications
Turn an article about rising costs into something readers can use.
(FAQ)
Widget questions
Prefer to send people to MarginShock instead? Link to the fuel surcharge calculator.
01Is the widget really free?
Yes. There's no account, key, or fee. The only requirement is the small 'by MarginShock' credit line under the widget, which is included in the code.
02Will it slow down my page?
The widget loads lazily in its own frame, so it doesn't block your page. The resize script is under 2 KB.
03How do I add it to WordPress, Wix, or Squarespace?
WordPress: add a Custom HTML block and paste the code. Squarespace: use a Code block. Wix: use Embed Code → Embed HTML, then drag the box tall enough for the calculator (Wix wraps embeds in a fixed-height frame).
04What happens to numbers visitors enter?
Calculations are stored anonymously, along with the name of the site the widget is on, to build industry benchmarks. Individual numbers are never published or sold, and no visitor contact details are collected. The widget says this under the calculate button.
05Can I change the colors?
There's a light and a dark theme. Keeping one consistent design keeps the widget simple and reliable everywhere.
06Does the diesel price update automatically?
Yes. It shows the U.S. Energy Information Administration's latest weekly average for the region you choose, refreshed automatically.