Calculators on a hand-coded site,
in five steps
Paste into your page, paste your snippet, publish, and test. This guide covers the clicks, the common snags and how to confirm leads arrive.
How do I add a calculator to a hand-coded HTML page?
Paste into your page on the page, paste the snippet from your calculator's Embed tab, and publish. The calculator loads from our servers, stays style-isolated from your theme, and works on mobile. No plugin is required.
Embedding on plain HTML
Open the page file
In your editor or CMS template.
Paste the placeholder
Put the placeholder div where the calculator should appear.
Add the loader once
Include the script tag once per page, ideally before </body>.
Deploy
Upload or deploy as you normally do.
Test
Load the page and run the calculator.
The snippet you'll paste
Copy the real one from the app; it contains your embed key.
<div data-calculator="rmd" data-key="YOUR_EMBED_KEY" data-mode="inline"></div>
<script src="https://app.numbersforclients.com/cf.js" async></script>Illustrative example. The loader script needs to appear only once per page.
Common problems and fixes
| Problem | Fix |
|---|---|
| Content Security Policy blocks the script | Allow the app origin in script-src, connect-src and frame-src. |
| Calculator inside a hidden tab | Calculators load when visible; switch to the tab to initialize. |
| Single-page app | Call the loader's scan after route changes, or use the framed mode. |
Static sites and custom builds have the most control. If you run a strict Content Security Policy, add the app origin to script-src, style-src, connect-src and frame-src.
plain HTML embedding questions
Do I need a plugin or app for plain HTML?
No. The snippet is plain HTML and JavaScript, so any block or element that accepts custom code works.
Where do I get my snippet?
In the app, open the calculator, go to the Embed tab and copy the snippet for the display mode you want.
Can I add several calculators to one page?
Yes. Paste each calculator's placeholder; the loader script only needs to appear once per page. Or use a widget.
The calculator doesn't appear. What should I check?
Confirm the code block allows JavaScript, that you published (not just saved) the page, and that the calculator is active in your account. Then try the framed mode.
Will the calculator use my site's fonts?
No, it's style-isolated. Set fonts and colors in the app so it matches.
Does the calculator work on mobile?
Yes, it's responsive. Preview the page on a phone before announcing it.
How do I test lead capture?
Submit the form with your own details and check that the contact appears in the app and the email arrives.
Can I put the calculator in a popup instead?
Yes, copy the popup button or floating snippet from the Embed tab.
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