The snippet
Paste this into your page HTML wherever you want the tool to appear:
<iframe src="https://difflists.site/embed/compare" width="100%" height="900" style="border:0;border-radius:12px" loading="lazy" title="Compare two lists"></iframe>
That’s it — no script tags, no build step, and it adapts to light or dark based on the visitor’s system preference automatically.
Live preview
Sizing it to your layout
The embed is responsive to width but has a roughly fixed content height once results are showing. 900px tall comfortably fits the tool and one full set of results without internal scrolling on most layouts; go shorter if you’re embedding above the fold and don’t mind visitors scrolling the page to see results.
What you’re linking to
The embed points at https://difflists.site/embed/compare, which includes a small “Powered by DiffLists” attribution link back to the site — please keep that link intact rather than hiding it with CSS.
Prefer to build your own integration?
If an iframe doesn’t fit your use case — for example, you want the comparison result as data in your own UI rather than a rendered widget — use the public API instead, which returns the same five results as JSON.
Is embedding DiffLists free?
Yes, no signup, no API key, and no usage fee for embedding the widget.
Does the embedded tool work the same as the full site?
Yes, it's the same comparison engine — difference, intersection, union, and symmetric difference — just without the site header and footer.
Will comparisons run inside my page send data to DiffLists?
No. Like the main site, the embedded tool runs entirely in the visitor's browser — nothing they paste is transmitted anywhere.
Can I resize the embed?
Yes, adjust the iframe's width and height attributes (or your CSS) to fit your layout. A minimum height of about 900px is recommended so the full tool is visible without internal scrolling.