Build a mix
- Paste a YouTube or YouTube Music link (a single song or a playlist) into the box above the playlist, or press Ctrl/⌘+V anywhere on the page. You can also add your own files (MP3, WAV, M4A, FLAC) with Add music or by dropping them on the page. Tracks play in order, top to bottom.
- On the timeline, drag a song's green edge to set where it starts and its red edge to set where it ends. Drag the ◆ to set how long it crossfades into the next song.
- For exact timing, use the Track editor. Type times like 1:23.40, nudge them 0.05 s at a time (hold Shift for 1 s), or click the waveform to preview from that point.
- Press Auto mix to play the whole set. Mix now starts the crossfade early, and Cut jumps to the next song straight away. Either one saves the new end point to the song.
- Use Export WAV to render the finished mix to a file, or Rec to capture a live performance with your EQ and fader moves.
Shortcuts
SpacePlay / pause the set
EnterMix now: start the transition at the current length
XCut: switch to the next song immediately
1 Play / pause deck A
2 Play / pause deck B
Q Set IN on deck A at the playhead (W sets OUT)
O Set IN on deck B at the playhead (P sets OUT)
← →Move the crossfader
+ −Zoom the timeline
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Party mode
Press Party and then Start a party on the device with the music. Other phones and laptops scan the QR code or type the 4-letter code to become extra speakers. Each speaker joins in 4 steps:
- Clock lock. It measures its clock against the party relay about 30 times, until it's accurate to a few milliseconds.
- Download. Every song in the set is copied to the device first, so it plays from its own copy.
- Scheduled entry. It proposes an exact start time on its own clock and a point in the song, and the host confirms them. When you press Auto mix, every ready speaker starts at the same moment.
- Fade-in. A speaker that joins mid-song fades in over 3 seconds.
The host’s Party panel shows every device with its status, level meter, ping, clock accuracy, sync error and a volume control. Phones and Bluetooth speakers add delay that browsers can’t see, so use Align by sound: the host plays test chirps, listens through its microphone, and corrects each speaker to the millisecond. YouTube tracks can’t be copied to speakers, so they only sync to about ±150 ms. Use your own files for a tight party.
Privacy
Your files stay on this device. Nothing is uploaded unless you start a party: then your own files go to a private party relay so the speakers can play them, and they’re deleted 12 hours after the party goes quiet. Each song's IN, OUT and fade settings are saved in this browser, so they come back when you add the same file or video again.
YouTube tracks
YouTube plays inside its own player, so the app controls its volume for fades and crossfades, but EQ, filter, tempo, waveforms and BPM aren’t available, and YouTube audio can’t be exported or recorded. Some videos are blocked from playing outside YouTube by their owners. On iPhone and iPad, iOS doesn’t let websites change YouTube’s volume, so fades there turn into cuts. Use a computer or Android for smooth YouTube mixes.