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Add Audio to Video Guide

Add a music track or voiceover to a video, replacing or mixing with the original sound.

Overview

Combine any video with any audio file. Replace the original soundtrack entirely, or mix the new track on top of the existing audio with adjustable volume. The video stream is copied without re-encoding, so quality is untouched and processing is fast.

Key Features

  • Replace or mix modes
  • Volume control for the added track
  • Video stream copied losslessly
  • Output trimmed to the shorter input

Use Cases

  • Adding background music to a clip
  • Replacing bad audio with a clean voiceover
  • Scoring screen recordings before sharing

How to Use

1

Upload your video

2

Upload the audio track

3

Choose Replace or Mix mode

4

Set the new track's volume

5

Process and download the MP4

Settings & Properties

Mode

Replace discards original audio; Mix blends both tracks

Volume

Gain applied to the added audio track

Ready to Get Started?

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