OneTaskBy Tim King · Updated
Reaction Video Recorder
Webcam Corner, Side-by-Side or Stacked Layout, Both Captured in One Video File
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How the Reaction Video Recorder works
This reaction video recorder plays any video next to your webcam and records both into a single file, with the clip's sound and your microphone mixed together. Add the video, start the camera, press Record and react. Recording stops when the clip ends, and the finished video is ready to download.
How the reaction video recorder works
The page draws the clip and your camera onto one canvas thirty times a second and records that canvas with your browser's built-in video recorder. The clip's audio and your microphone are mixed in the browser, so the download already has both voices in sync and needs no editing.
Layouts
The four corner layouts show the clip full frame with your webcam in a framed box, which is the classic YouTube reaction look. Side by side gives each picture half of a 1280 × 720 frame. Stacked puts the clip on top and your face below in a 720 × 1280 portrait frame for TikTok, Reels and Shorts.
Getting good sound
Wear headphones. Without them your microphone hears the clip through the speakers and records it a second time, a fraction of a second late, which sounds like an echo. Use the video volume slider to keep the clip quieter than your voice; 60 to 80% usually works.
Copyright
Reacting to someone else's video can fall under fair use or fair dealing when you add real commentary, but platforms still match audio and pictures. Short clips, plenty of your own talking, and permission from the creator are the safest route.
FAQ
Is my webcam recording uploaded anywhere?
No. The camera, the microphone, the clip and the finished recording all stay in your browser. The file is only created on your device when you stop recording, and nothing leaves it unless you upload the download yourself.
Why does my reaction video have an echo?
Your microphone is picking up the clip from your speakers as well as the clean copy mixed in directly. Plug in headphones or earbuds and record again. Echo cancellation helps a little, but it cannot fully remove sound that plays loudly in the room.
What format is the reaction video saved in?
Chrome and Edge save WebM or MP4 depending on version, Safari saves MP4 and Firefox saves WebM. If an app will not accept WebM, run the file through a video converter first. The frame is 1280 × 720, or 720 × 1280 for the stacked layout.
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