Options
- Responsive — 100 % width so the embed fits phones.
- loading="lazy" — the frame loads only when scrolled into view, which helps page speed.
- title — required for screen readers.
- sandbox — restricts what the embedded page can do (recommended for third-party content).
- allowfullscreen — for videos and presentations.
Some sites refuse to be embedded (X-Frame-Options or CSP frame-ancestors); their frame will stay blank. Test embeds in the HTML Viewer.
Frequently asked questions
Why is my iframe blank?
The embedded site probably blocks framing with X-Frame-Options or Content-Security-Policy.
Are iframes bad for SEO?
Content inside an iframe belongs to the embedded page, not yours; use iframes for widgets, not your main content.
How do I keep a 16:9 ratio?
Add style="aspect-ratio:16/9;height:auto" with width 100%.

