Applies to the WatchParty browser extension and the WatchParty server it connects to. Last updated: 31 October 2026.
WatchParty is a private, self-hosted tool for watching YouTube in sync with friends. It is run by an individual for their own friends and is not a public service. It does not sell or share your data, and uses it only to make the shared playback work.
Only while you are in a room, the extension sends to the server named in its settings: the display name you chose, a random identifier generated by the extension, the room code, the YouTube video you are watching (its address and id), and playback state (playing or paused, position, speed, and whether your player is buffering or showing an ad). This is needed to keep everyone's player in step and to show the other people in the room who is there. The extension does not read or change any page other than YouTube, and on YouTube it only controls the video player and shows the WatchParty banner and tab icon.
Like any server, the server also sees the IP address your connection comes from (relayed via Cloudflare).
In the server's memory: rooms and everything above, only while a room is in use. It is discarded when the room is empty or the server restarts. The owner can mark a room to be kept, in which case its code, video and position are saved on the server's disk until they stop keeping it.
On the server's disk: a list of the installs that have connected, so the owner can see who uses the server and block abuse: the random identifier, the last name used, the most recent IP address, the first and last time seen, how many times it connected, and any private note or block the owner added. It is visible only to the server's owner, on their local network. It is kept until the owner removes it.
On your device: the extension stores your name, server address, the random identifier and a list of rooms you named, in your browser's extension storage. Removing the extension deletes it.
Your name and playback state are visible to the other members of your room. Nothing is shared with anyone else: there are no accounts, no analytics, no advertising, no data brokers and no third-party services (apart from Cloudflare, which relays the connection to the server).
Connections to the server use encrypted transport (HTTPS / WSS). The administration page that shows the list above is only reachable from the owner's local network.
You can stop at any time by leaving the room or removing the extension. To ask what the server has stored about you, or to have it deleted, contact the person who invited you to use WatchParty.
If this policy changes, the date above is updated.