How to Set Up a Reaction Video View with Two YouTube Videos in Sync

Watch a reactor and the source video in perfect sync. Load both into DualTube, align the moments, and never scrub back to see what the reactor was reacting to.

Try it now

Open DualTube→
  1. 1

    Open the reaction video

    Grab the YouTube URL of the reaction video and paste it into the left player.

  2. 2

    Find the original source

    Most reactors link the original in their description. Paste it into the right player.

  3. 3

    Sync start points with offset

    Reactors usually have 30–90 seconds of intro. Use the offset slider to shift the source so both start the actual content simultaneously.

  4. 4

    Use audio balance to pick a side

    Center for both mixed, or slide all the way to one side when the reactor is talking vs when the source is loud.

  5. 5

    Save and share the setup

    Click Save to keep the configuration. Share the URL with friends — the offset is encoded in the link.

Frequently Asked Questions

Is this legal?▾

Yes. You are watching two embedded YouTube videos through the official YouTube IFrame API. No downloading, no rebroadcasting.

What if the reactor muted the source?▾

Slide audio balance fully to the source side to hear it directly. You can rebalance any time.

Can I pause both at once?▾

Yes — a single play/pause control drives both players, so nothing drifts.

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