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Koenpk's avatar
Koenpk
Iron Contributor
Aug 03, 2026

How can I add music or audio to video without watermark?

I am editing a video on my Windows 11 laptop and plan to post it on TikTok. I want to add some background audio from my PC to the video. Is there a simple way available for doing this? I tested a few...
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MateoZhang's avatar
MateoZhang
Copper Contributor
Aug 03, 2026

MKVToolNix provides a reliable method to combine video and separate audio streams, making it an excellent tool to add audio to video without watermark. It performs fast multiplexing with no video re-encoding, so there is no quality loss and minimal risk of audio sync issues.

How to Add Audio to Video Without a Watermark

Step 1: Drag and drop your MP4 video file and separate audio file into the Source Files pane.

Step 2: Uncheck any original, unwanted audio tracks displayed in the track list at the bottom.

Step 3: Confirm the output file name and destination folder.

Finally, click Start Merging. The new merged media file will be generated quickly—usually in less than 3 seconds.

For users looking for a desktop tool to add audio to videos without watermarks, this software is a reliable open-source option. Multiplexing technology eliminates the need for time-consuming re-rendering and fully preserves the original media quality.

Pros

  • Open source; extremely fast stream merging
  • No re-encoding required; fully preserves original video and audio quality
  • Supports adding, removing, and reordering multiple subtitles and audio tracks

Cons

  • Default output format is MKV; does not support direct export to MP4
  • No built-in video editing features; provides only stream multiplexing
  • The interface may seem overly technical