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Audio Merger

Merge multiple audio files into one

Click to upload multiple audio files

About Audio Merger

Audio Merger joins two or more audio files into one, using ffmpeg's stream-copy concat feature entirely in your browser via ffmpeg.wasm — nothing is uploaded to a server. Files are combined in the order you select them; there's no drag-to-reorder, fade, or volume-leveling controls.

How to use Audio Merger

  1. 1Click the upload area and select two or more audio files — they'll merge in the order you pick them.
  2. 2Review the list of selected files.
  3. 3Click "Merge Audio Files" to combine them locally.
  4. 4Preview and download the merged MP3.

Frequently Asked Questions

Can I reorder files before merging?

Not currently — files merge in the order they were selected during upload.

Does merging work with mixed formats?

It works best when all files share the same codec/format, since the process uses fast stream-copy rather than re-encoding; mixing very different formats can sometimes fail.

Is there a limit on file count or size?

No hard limit is enforced by the tool — you're limited by your browser's available memory.

Is my data private?

Yes. Everything happens locally via ffmpeg.wasm — files are never uploaded to a server.

Tips & Tricks

  • ✓For the most reliable results, merge files that share the same format and bitrate (e.g., all MP3 at 128kbps).
  • ✓Double-check the file order in the list before merging, since there's no drag-to-reorder — remove and re-add files in the order you want if needed.
  • ✓If merging fails, try converting all files to the same format first with the Audio Converter tool.
  • ✓The first merge after loading the page takes longer since the ffmpeg.wasm engine needs to download.