Join audio files online — free MP3 merger

Join and merge multiple audio files into a single MP3 directly in your browser, with no uploads and no sign-up. This free online audio joiner combines MP3, WAV, OGG, M4A and FLAC clips end-to-end in the exact order you add them, re-encoding mixed formats so they join cleanly into one seamless MP3. It is perfect for stitching together voice memos, podcast segments, audiobook chapters, lecture recordings or song parts into one continuous track. Because everything runs locally using WebAssembly, your audio files never leave your device — nothing is ever uploaded to a server. Just add your clips, check the order, and download the merged MP3 in seconds.

🔒 100% private — files never leave your device

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How to use

  1. Add two or more audio files (MP3, WAV, OGG, M4A or FLAC) you want to join.
  2. Check the order — files are joined end-to-end in the order they were added.
  3. Click Join and let the tool merge them into one MP3 in your browser.
  4. Download your combined MP3 file — no upload, no watermark, no sign-up.

Frequently asked questions

What audio formats can I join?

You can join MP3, WAV, OGG, M4A and FLAC files. You can even mix different formats in one job — the clips are re-encoded so they merge cleanly into a single MP3 output.

Are my audio files uploaded anywhere?

No. Everything runs 100% locally in your browser using WebAssembly. Your audio files are never uploaded to a server and never leave your device.

In what order are the files joined?

Files are joined end-to-end in the exact order you add them. Add them in the sequence you want them to play so the final MP3 plays in the right order.

How many audio files can I merge at once?

You need at least 2 files to join, and there is no fixed upper limit. Since processing happens on your own device, very large batches or long files depend on your computer's memory and speed.

Will merging reduce the audio quality?

The clips are re-encoded to MP3 so that files with different formats and sample rates join seamlessly. The result is a standard MP3, so any quality change is only the normal effect of MP3 encoding.

Why does the first run take a moment?

The audio engine is a one-time download of about 30 MB on the first run. After that it is cached in your browser, so joining files is fast and works even offline.

About this tool

Free online audio joiner to merge MP3, WAV, OGG, M4A and FLAC files into a single MP3. Runs 100% in your browser with no uploads — your audio stays private.

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