Does the iframe embed work on WordPress?

Yes. Paste it into a Custom HTML block, a Code block, or directly in the post HTML. WordPress's stripping of script tags doesn't affect iframes.

Does it work in an LMS like Teachable, Thinkific, Kajabi?

Yes. All major LMS platforms support iframe embeds. Some have a dedicated 'video embed' block; others accept raw HTML — both work.

What about Notion, Substack, Ghost, Bubble?

Notion supports iframe embeds via the /embed slash command. Substack supports iframes in paid newsletters. Ghost has a custom HTML block. Bubble has an HTML element. All work.

Iframe Embed Code

Every video on AVCaption gets a single iframe code:

<iframe
  src="https://avcaption.com/watch/{your_embed_token}"
  frameborder="0"
  allow="autoplay; encrypted-media; fullscreen"
  allowfullscreen
  loading="lazy"
  width="100%"
  style="aspect-ratio: 16/9"
></iframe>

Paste it on any platform that accepts HTML. That’s it.

Where it works

CMS / Blog

WordPress (Custom HTML block, Code block, raw post HTML)
Ghost (HTML card)
Substack (HTML in posts, including paid posts)
Medium (limited — bookmark cards only, no iframe)
Hashnode (Embed block)

LMS / Course platforms

Teachable (Video block accepts iframe code via “Custom Code”)
Thinkific (Custom Code block)
Kajabi (HTML block in posts and product pages)
LearnDash (HTML in lesson body)
LearnWorlds (Embed block)
Podia (Custom HTML)

No-code builders

Webflow (Embed element)
Bubble (HTML element)
Wix (HTML iframe block)
Squarespace (Code block)
Carrd (Embed section)
Framer (Embed component)

Productivity / Knowledge

Notion (/embed slash command)
Coda (Embed)
ClickUp (Embed view)

Email — limited. Most email clients block iframes (Gmail, Outlook). Send a link with og:image preview instead.

URL parameters

Append query parameters to the iframe src:

?autoplay=1&muted=1 — start playing on load (muted required for autoplay)
?start=120 — seek to 120s
?subtitle=vi — preselect Vietnamese subtitle
?quality=1080 — force 1080p variant
?loop=1 — restart on end
?controls=0 — hide all controls (kiosk mode)

Combine multiple: ?autoplay=1&muted=1&start=30&subtitle=es.

Security headers

The iframe responds with:

Content-Security-Policy: frame-ancestors {your_whitelist} — browsers block embedding on non-whitelisted origins
Referrer-Policy: strict-origin — referrer info limited to scheme+host
Permissions-Policy: autoplay=*; fullscreen=* — needed for the allow attribute to work

You don’t configure any of this — AVCaption sets the right headers based on your domain whitelist.

Performance

First paint: 600-900ms on 4G mobile, sub-300ms on broadband
HLS.js + player JS: ~60KB minified+gzipped
First segment pre-warmed at upload time, served from CDN edge
loading="lazy" defers iframe load until user scrolls near it (recommended)

Responsive sizing

The iframe is fully responsive when you use width="100%" and aspect-ratio: 16/9. The video scales to its container, which is what you want on most sites.

For a fixed pixel size: width="800" height="450" (or any 16:9 ratio).

For non-16:9 (e.g. 4:3 archival video): set aspect-ratio: 4/3 to match the source.

Get started

Every video uploaded to AVCaption has an iframe code on the video detail page. Upload one test video, copy the iframe, paste it into a Notion doc or a draft blog post — the embed renders the same way it will on Teachable, Kajabi, Confluence, Salesforce Community pages, or your custom site. Common production embed targets: LMS video hosting, online courses, digital products.

Iframe Embed Code — One Tag, Every Platform