Calories Burned Calculator for your website
Energy burned by an activity from its MET value, body weight and duration. Net of what you would have burned sitting still, which trackers leave in. Set the values it should open on, then copy the iframe. Your visitors can change them; the widget recomputes against Rule Calculator and never touches your page.
Who puts this on their site
Fitness sites and activity trackers, using the MET values the ACSM compendium publishes rather than a made-up table.
Free for commercial use. No key, no account, no tracking script, and nothing loaded from a third party — the iframe points at Rule Calculator and that is the only request it makes. The formula and its source travel with it, so the number on your page is one your readers can check.
Opening values
Set what the widget shows before anyone touches it. Leave a field as it is and it stays out of the URL.
Preview
Paste this
<iframe src="https://rulecalculators.com/embed/calories-burned" width="100%" height="720" style="border:1px solid #e5e5e5;border-radius:12px" loading="lazy" title="Calories Burned Calculator"></iframe>
<p style="font:13px/1.5 system-ui,sans-serif;color:#666;margin:6px 0 0"><a href="https://rulecalculators.com/calc/calories-burned" style="color:#666">Calories Burned Calculator</a> by <a href="https://rulecalculators.com" style="color:#666">Rule Calculator</a></p>Free for commercial use. The one condition is the credit link inside the widget, which is how the calculator stays free. Want the numbers in your own markup instead? The same calculator is a JSON endpoint, or see the full Calories Burned Calculator page with its sources and working.