Questions and answers

Yes. There is no paid tier, no trial period, and no feature gating. You do not need an account or an email address. Create a room, share the code, and watch.

No. PartyStream runs entirely in the browser. Guests join by entering a room code or clicking an invite link. No app, no extension, no download. It works on Chrome, Firefox, and Safari on desktop and mobile.

When the host creates a room, the server generates a random 8-character code. The host shares this code (or a direct invite link) with whoever they want to join. There is no public room directory. Without the code, nobody can find or enter the room. Room codes are case-insensitive.

Yes. The host clicks "Paste a YouTube link" on the drop zone, pastes any YouTube URL, and the video loads for everyone in the room. Each person's browser loads the video from YouTube independently, so there is no quality loss from re-encoding. Play, pause, and seek are synced across everyone through Socket.IO. YouTube's own controls (volume, quality, fullscreen) are available to each viewer.

PartyStream streams up to 1080p. If the host loads a 4K file, it gets capped at 1080p before sending to guests. Each guest can pick their own quality setting: Auto (adjusts to your connection), High (full 1080p), Medium (roughly 720p), or Low (roughly 360p). Auto mode watches your inbound bitrate and drops or raises quality on the fly, so guests on slower connections still get a watchable stream.

The host picks a video file from their computer, pastes a YouTube link, or shares their screen. For files and screen shares, PartyStream streams directly to each guest through WebRTC, a peer-to-peer protocol built into modern browsers. The video never touches a server. For YouTube links, each person's browser loads the video from YouTube independently and sync is handled through Socket.IO. A separate signaling server (Socket.IO) handles room management, chat, and sync commands, but it never sees your video data.

MP4 (H.264 + AAC) works best. WebM (VP8 or VP9 with Opus audio) also works. Other containers like MKV, MOV, or AV1 files may not stream because the browser's captureStream API only works with formats it can decode natively. If you hit an "unsupported format" error, converting to MP4 usually fixes it.

Up to 4 guests per room, plus the host. The host uploads a separate stream to each guest, so the host's upload bandwidth is the bottleneck. With 4 guests at 10 Mbps each, the host needs roughly 40 Mbps of upload. If your connection is slower, guests can drop to Medium or Low quality to reduce the bandwidth demand.

Every play, pause, and seek command from the host gets broadcast to all guests through Socket.IO. The sync precision is under half a second. If a guest's playback drifts, the host periodically sends the current timestamp so stragglers can catch up. Guests cannot independently control playback; only the host can play, pause, or seek.

No. The file stays on the host's computer and streams directly to guests through WebRTC. PartyStream's servers handle signaling (room creation, chat messages, sync commands) but never receive, store, or process your video data. Once the room closes, nothing is saved.

Chat requires an active connection to the signaling server. If a guest loses their connection, they cannot send or receive messages until they reconnect. Messages are not stored or queued. When you join a room, you only see messages sent after you joined.

Yes, on the guest side. Guests can join from any mobile browser. The host needs a desktop browser because they are encoding and uploading the stream in real time, which requires more processing power than a phone typically handles well. The interface adapts to smaller screens: sidebars become overlays, and video controls are always visible on touch devices.

Guests lose the stream. The host is the source, so there is no fallback. The video player shows a disconnected state, and chat continues to work. If the host reconnects, they can resume from where they left off. PartyStream does not record or buffer the video server-side, so there is no way to recover a stream after a disconnect.

That depends on the DRM. Most purchased or rented movies from services like iTunes, Google Play, or Amazon Prime use DRM protection that prevents captureStream from working. PartyStream works with DRM-free video files: home videos, personal recordings, downloaded creative-commons content, or screen recordings you made yourself.