Turn any video into a watch party.

Watch videos together remotely. No account, tracking, or ads. Share a link and start together.

A cute koala standing and looking down at the download buttons v3.0.2 is out! 🎉 See what's new → v3.0.2 ist da! 🎉 Was ist neu? →
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Free · Open source · No account needed

A cute koala juggling multiple browser tabs showing streaming platforms

Works on your favorite platforms

Why KoalaSync?

Built for reliable sync, privacy-first design, and easy setup.

Two cute koalas sitting together and sharing a bucket of popcorn

Movie Night with Friends

Sync your movies in real time and talk via Discord, Zoom, or your favorite voice call application. It feels just like sitting in the same room.

A koala professor presenting on a screen to two remote student koalas

Remote Learning

Review tutorials, lectures, or training videos together. Pause and discuss complex steps as a group.

A cute koala couple watching together remotely; one is sitting at a PC and the other is in bed with a laptop, with flying hearts between them

Long-Distance Relationships

Bridge the distance and enjoy date nights. Experience every plot twist, laugh at the same jokes, and share emotional moments at the exact same millisecond.

Features

Instant Invites / 1-Click Join

No IP addresses or passwords to exchange. Share a generated invite link with your friends to let them join your room automatically with a single click.

Volume Leveling / Audio Compressor

No more riding the volume knob. A built-in compressor lifts quiet dialogue and tames loud explosions, all processed locally in your browser.

Universal HTML5 Support

Netflix, YouTube, Twitch, Jellyfin, Emby and almost any page with an HTML5 video. Only sync signals leave your browser, never the video.

A cute koala weighing options in both hands to compare KoalaSync vs Teleparty

KoalaSync vs. Teleparty

See why open source, ad-free and privacy-first is the superior way to watch together.

Feature KoalaSync Teleparty
Cost / Paywalls Premium subscriptions, hidden fees or locked features. ✔ 100% Free ✘ Paid Tiers / Premium Locks [1]
License / Code Auditable Whether the source code is open and freely auditable. ✔ Open Source (MIT) ✘ Proprietary [2]
Self-Hosting Ability to deploy your own private relay server. ✔ Yes (Docker-ready) ✘ No [2]
Privacy & Tracking Registration requirements, tracking cookies and analytics. ✔ Zero-Persistence (RAM-only) ✘ Google Analytics & Cookies [2]
Site Compatibility Supported websites and player compatibility. ✔ Almost any HTML5 Video[3] ✘ Supported sites only [1]
Localization / Translation Available interface languages and translation support. ✔ 15 Languages (and growing) ✘ English only
Audio Compressor / Volume Leveling Built-in audio normalization to balance quiet dialogue and loud effects ✔ Yes (4 presets, dry/wet control) ✘ No

Comparison state: May 2026.

[1] Official Teleparty Premium pricing and supported networks details: teleparty.com/premium

[2] Teleparty privacy policies and tracking data collection: teleparty.com/privacy

[3] Works on websites that allow script injections into standard HTML5 video tags. Websites with highly strict Content Security Policies (CSP), DRM copy protection, or heavily obfuscated player wrappers (like complex shadow DOMs) might restrict automated control or injection.

Full comparison and more alternatives

Getting Started

Create & Share Room

Open the extension popup, create a room with one click, and share the link with your friends. They join instantly via the invitation bridge.

KoalaSync Logo KoalaSync
3.0.2
Room
Sync
Settings
+ Create New Room
▶ Manual Connect / Advanced

Select Video Tab

Go to your video tab and select the tab you want to synchronize in the popup. KoalaSync automatically links your playheads from here.

KoalaSync Logo KoalaSync
3.0.2
Room
Sync
Settings
👆
▶ Play
⏸ Pause

Watch Together

Press play. Playback changes are shared with everyone in the room; network and player conditions can cause a brief delay.

🐱 ChillCat PLAYING
⏸
42:15
IN SYNC
🐶 HappyDog PLAYING
⏸
42:15

For Self-Hosters

Don't trust our server? Maintain full data sovereignty. Deploy your own private relay server in minutes.

A cute koala sitting at a laptop deploying a Docker container for self-hosting
Show setup guide Hide setup guide 
services:
  koala-sync:
    image: ghcr.io/shik3i/koalasync:latest
    container_name: KoalaSync
    restart: unless-stopped
    environment:
      TZ: Europe/Berlin
      PORT: 3000
      MIN_VERSION: 1.0.0
      MAX_ROOMS: 100
      MAX_PEERS_PER_ROOM: 25
      # Required: replace before starting
      SERVER_SALT: "REPLACE_WITH_OPENSSL_RAND_BASE64_32_OUTPUT"
      # Optional: leave empty or replace with a 32+ character token
      ADMIN_METRICS_TOKEN: ""
      DEBUG_LOGGING: "0"
    # Host Caddy reaches the relay only through this loopback binding
    ports:
      - "127.0.0.1:3000:3000"
    pids_limit: 2048
sync.koalastuff.net {
    root * /var/www/koalasync/website/www
    encode zstd gzip
    
    # Clean URLs support (no .html required)
    try_files {path} {path}.html {path}/
    file_server
}

syncserver.koalastuff.net {
    reverse_proxy localhost:3000
}
(security_headers) {
    header {
        # Enable HTTP Strict Transport Security (HSTS)
        Strict-Transport-Security "max-age=31536000; includeSubDomains; preload"
        # Prevent clickjacking attacks (Sameorigin)
        X-Frame-Options "SAMEORIGIN"
        # Prevent MIME-sniffing
        X-Content-Type-Options "nosniff"
        # Enable browser XSS protection
        X-XSS-Protection "1; mode=block"
        # Control referrer information
        Referrer-Policy "strict-origin-when-cross-origin"
        # Hide Caddy server stamp signature
        -Server
    }
}

sync.koalastuff.net {
    encode zstd gzip
    root * /var/www/koalasync/website/www

    # Clean URLs: Resolves paths without .html in the URL
    try_files {path} {path}.html {path}/
    file_server

    # Static Caching for high performance
    @static {
        file
        path *.ico *.css *.js *.png *.svg *.webp *.avif
    }
    header @static Cache-Control "public, max-age=31536000, must-revalidate"

    # Hardened Security & Permission Policies
    import security_headers
    header {
        Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; connect-src 'self'; img-src 'self' data:; object-src 'none'; frame-ancestors 'none'; base-uri 'none'; form-action 'none';"
        Permissions-Policy "camera=(), microphone=(), geolocation=(), payment=(), usb=()"
    }
}

syncserver.koalastuff.net {
    import security_headers
    encode zstd gzip
    reverse_proxy localhost:3000
}
A cute koala holding a question mark wondering about KoalaSync

Frequently Asked Questions

Answers about supported sites, synchronization, privacy, chat and audio processing.

Show all questions Hide questions
Can I watch Netflix, Emby or Jellyfin together in sync with friends?

KoalaSync works with many supported websites that use a standard browser video player, including Netflix, YouTube, Twitch, Emby, Jellyfin and self-hosted media servers. Compatibility depends on the website, browser and player and can change when a site updates.

Does KoalaSync stream the video to my friends?

No. KoalaSync does not stream, host, share, or bypass access to video content. Everyone watches the video locally in their own browser and needs their own access to the website or streaming service, such as their own Netflix account. KoalaSync only synchronizes playback actions like play, pause, and seeking.

Is KoalaSync a free alternative to Teleparty?

Yes. KoalaSync is free and open source under the MIT License, with no premium tier, locked features, ads or required user account.

Does KoalaSync work with Emby, Jellyfin and self-hosted media servers?

Yes. KoalaSync supports many standard browser video players used by Emby, Jellyfin, Plex and custom self-hosted streaming setups. Compatibility depends on the player. You can also self-host the KoalaSync relay server with Docker.

Which browsers and platforms support KoalaSync?

Google Chrome, Mozilla Firefox, Microsoft Edge, Opera, Brave, and all Chromium-based browsers. Install it directly from the Chrome Web Store or Firefox Add-ons, no manual configuration needed.

Do all my friends need the extension installed?

Yes, each participant needs KoalaSync installed, but there's no sign-up or account creation. Simply click the invitation link, install the extension if you haven't already, and you'll join the room automatically in seconds.

Is my data safe? What if I don't trust the official server?

The official KoalaSync relay does not store room, sync, watch, or chat history in a database. Active room data exists temporarily in memory and is removed when the room becomes empty or expires after inactivity. Technical connection logs may be created for security and abuse prevention; their retention depends on the server configuration. Chat messages are end-to-end encrypted and are not stored as server-side history. You can also self-host the relay with Docker.

Can I fix quiet dialogue and loud explosions when watching videos in the browser?

Yes. KoalaSync includes an audio compressor that reduces the difference between quiet and loud parts of a video. It runs locally through the Web Audio API, so audio data is not sent to the relay. Open the popup, create or join a room, then enable it under Settings → Audio Processing.

Need help? Open the Help Center

Not convinced? See for yourself.

KoalaSync is 100% open source, ad-free and tracking-free. Audit our codebase on GitHub or install the browser extension directly.

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