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Audio Joiner

Combine several tracks in order, with optional per-track in/out, crossfade or silence gaps.

Browser-first · upload only when a format needs it

Combine several tracks in order, with optional per-track in/out, crossfade or silence gaps.

Opens MP3 · WAV · M4A · FLAC · OGG · AAC · MP4 · WEBM · MOV · MKV

This tool needs at least 2 files.

or drop files and folders hereUp to 500 MB per file on the free plan · older formats use the server encoderFolders are welcome

How it works

  1. 01

    Choose a file for Audio Joiner. It accepts MP4, MOV, WEBM, MKV, MP3, WAV, FLAC, OGG, M4A. Most files stay in this tab.

  2. 02

    Set the options on the workbench — preview, crop or timeline when this tool has one — then press Run.

  3. 03

    Download the result. It is also saved in your tray so the next tool can pick it up without another upload.

About this tool

Add the files in the order you want, pick a crossfade — none for spoken word, half a second to two seconds for music — and choose an output format. Files with different sample rates, channel counts or codecs are decoded and resampled to the first file, so a WAV, an M4A and an MP3 join cleanly into one MP3 or FLAC.

Questions

What can I open in Audio Joiner?
Audio Joiner accepts MP4, MOV, WEBM, MKV, MP3, WAV, FLAC, OGG, M4A. Older video containers such as AVI, WMV, FLV, MPEG and 3GP are decoded by the server encoder.
Does Audio Joiner upload my file?
Most MP4, WebM, images and PDF stay in this tab. Instagram/TikTok crops, DVD, GIF, iPhone presets, stabilize, hard containers (AVI, WMV, HEVC) and a failed local encode go to the server encoder. The file is processed and discarded — we do not keep a copy.
How large can the file be?
Free: 500 MB and 8 exports a day. Plus (waitlist) raises the daily cap. A pasted public file URL is also accepted.

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