ToolsVideo & Audio

Private browser workspace

Add Audio to Video

Add or mix a local audio track with a local video and export a browser-friendly MP4 using FFmpeg WebAssembly.

Free to use Your selected media stays on this device. The FFmpeg WebAssembly runtime downloads only when processing starts and works in temporary browser memory.

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How it works

Complete the job in three clear steps

  1. Choose the required local file or enter the requested values.
  2. Review the settings and start the explicit processing action.
  3. Inspect and download the result before closing the page.

Important

Check the result before relying on it

Keep an untouched copy of important source files. Browser processing depends on available device memory, and you should inspect every downloaded result before deleting the original.

Practical details

What this Lucaden tool does

Add or mix a local audio track with a local video and export a browser-friendly MP4 using FFmpeg WebAssembly.

The workspace names the actual engine, keeps source files out of Lucaden storage, and exposes important format or acceptance limitations.

Included capabilities

  • Replace or mix audio
  • AAC output
  • Original video stream copy
  • Shortest-duration control

Useful for

  • Add narration
  • Add background music
  • Replace a camera track
  • Prepare a social clip

Questions

About this tool

Does Lucaden store my working input?

No. The workspace uses temporary browser memory. Any optional direct destination request occurs only after you click its send action.

Should I keep the original file?

Yes. Check the exported result in the receiving application before replacing or deleting the source.

Open-source foundations

Built transparently

Lucaden documents its standards sources, architectural references, and permissive runtime dependencies while keeping this workspace consistent with the Lucaden interface.