Audio Joiner

Merge several audio files into one. Add files in the order you want, then export a single MP3, M4A, or WAV.

Local processing only — your files never leave the browser

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Drag & drop audio files, or tap to select (2 or more)

MP3 / WAV / M4A / AAC / FLAC / OGG, 200 MB total

Output format

Files are joined in the listed order and re-encoded to a single track, so clips with different formats or sample rates merge cleanly. Use the arrows to reorder.

Joining… 0%

Download merged audio

What this tool does

Combine any number of clips in the order you choose; reorder with the up/down arrows
Handles mixed formats and sample rates by re-encoding to one clean output
Export MP3, AAC/M4A, or lossless WAV
Accepts MP3, WAV, M4A, AAC, FLAC, OGG inputs, up to 200 MB total
Runs locally with ffmpeg.wasm — your files never leave your device

How to use

1
Add your files
Drop or select two or more audio files. They appear in a reorderable list.
2
Set the order
Use the ▲▼ buttons to arrange the clips; remove any with ✕.
3
Pick the output format
MP3 for compatibility, M4A for Apple, WAV to stay lossless.
4
Join and download
The clips are concatenated into one track. Preview, then download.

What each setting means

File order

Clips are joined top-to-bottom in the list order. Reorder before joining.

Output format

The single merged file is re-encoded to this format. WAV is lossless; MP3/M4A use 192 kbps.

Common pitfalls

Symptom: There is a click or gap between clips

Cause: The source clips have different sample rates or end on a non-zero sample.

Fix: Re-encoding to one output (what this tool does) removes most issues; for perfectly gapless joins, export the sources at the same sample rate first.

Symptom: The merge runs out of memory

Cause: Total input size is too large for the browser tab.

Fix: Keep the combined size under ~200 MB; convert long clips to a lower bitrate first.

Symptom: A file was ignored when added

Cause: It was not recognized as audio (unsupported extension or empty MIME type).

Fix: Use a common audio format (MP3/WAV/M4A/FLAC/OGG); extract audio from video with the Audio Extractor first.

Equivalent FFmpeg commands

Reference commands you can run on the desktop FFmpeg CLI.

Join 3 files (any formats) to MP3

ffmpeg -i a.mp3 -i b.wav -i c.m4a -filter_complex "[0:a][1:a][2:a]concat=n=3:v=0:a=1[out]" -map "[out]" -c:a libmp3lame -b:a 192k joined.mp3

Same-format lossless join (concat demuxer)

ffmpeg -f concat -safe 0 -i list.txt -c copy joined.m4a

Browser support & limits

Runs in the browser, so the combined input is limited to ~200 MB.
Inputs are re-encoded; for a bit-exact lossless join of identical formats, the CLI concat demuxer with -c copy is better.

Privacy

This tool runs ffmpeg.wasm directly in your browser. Files never leave your device — everything runs locally. Read the privacy policy →

Frequently asked questions

Can I join files of different formats?

Yes. The tool decodes each input and re-encodes them into one track, so mixing MP3, WAV, and M4A works fine.

Does it re-encode, or join losslessly?

It re-encodes to a single output so mixed inputs merge cleanly. Choose WAV output if you want a lossless result.

How many files can I merge?

As many as fit within the ~200 MB total-size limit of in-browser processing.

Can I reorder the clips?

Yes — use the ▲ and ▼ buttons in the file list to set the play order before joining.

Are my files uploaded?

No. Joining happens entirely in your browser via ffmpeg.wasm; nothing is sent to a server.