YouTube Live Chat Overlay

YouTube Live Chat Overlay (Lua Script)

This lightweight OBS Studio Lua script automatically embeds your YouTube Live Chat as a clean, customizable Browser Source with no third-party websites and no external applications. Just paste your YouTube Live Video ID and the script creates (or updates) a ready-to-use chat overlay inside OBS.

What It Does

The script creates or updates a Browser Source named “YouTube Chat Overlay” and loads your chat using the official YouTube pop-out chat URL format. It is designed for overlays: transparent background, optional UI cleanup, and full styling control through custom CSS.

Features

• Auto source management: creates or updates a Browser Source named “YouTube Chat Overlay”
• Video ID driven: automatically loads the correct chat for your live stream
• Transparent background: ideal for seamless scene overlays
• Hide YouTube UI chrome: optionally remove header, input box, and other non-overlay elements
• Scrollbar controls: optionally hide scrollbars or lock scrolling entirely
• Custom CSS field: restyle the chat freely (fonts, colors, spacing, badges, emotes, etc.)
• No dependencies: pure Lua, runs entirely inside OBS

How It Works

YouTube Live Chat can be embedded using the pop-out URL format:

https://www.youtube.com/live_chat?is_popout=1&v=VIDEO_ID

This script simply builds that URL from your provided Video ID and applies it to an OBS Browser Source. You can keep the default look for a clean, minimalist overlay or inject your own CSS to match your stream branding.

Setup in OBS

1. Open OBS Studio.
2. Go to Tools → Scripts.
3. Click the + button and add the .lua script.
4. Paste your YouTube Live Video ID in the script settings.
5. Choose your options:
   • Hide UI chrome (header/input)
   • Hide scrollbars or lock scrolling
   • Add custom CSS (optional)
6. Add the source to your scene: Sources → + → Browser → select “YouTube Chat Overlay”.

Customization (CSS)

Use the Custom CSS field to fully control the overlay’s look and readability. Common tweaks include:

• Increase font size and line spacing for large screens
• Improve contrast for dark/light themes
• Reduce padding so more messages fit
• Hide elements you don’t want on stream (timestamps, badges, etc.)

Best Use Cases

• Minimal chat overlays: clean chat look without YouTube’s extra UI
• Brand-matched layouts: restyle chat to match your graphics package
• Full-screen scenes: large readable chat for IRL or community streams
• Moderation-friendly: keep chat visible for hosts while recording or streaming