How to join audio files
- Drop two or more audio files on the box, or choose them from your device. Add more at any time.
- Drag the tracks into the order you want, or use the arrow buttons on each one.
- Choose what goes between tracks: nothing, silence, or a crossfade, and how long it lasts.
- Pick a format, press Join, listen to the preview, and download the file.
If the files have different sample rates or one is mono and another stereo, they are matched automatically. The result uses the sample rate of the first track.
Questions
Are my audio files uploaded?
No. Every file is decoded and joined inside this browser tab and never leaves your device.
Which formats can I join?
You can add MP3, WAV, OGG, Opus, FLAC, M4A, and AAC files, and even the sound of a video file, and mix them in one project. The result can be saved as MP3, WAV, M4A, or OGG.
What is a crossfade?
A crossfade fades the end of one track out while the start of the next fades in, so they overlap instead of stopping and starting. It suits music and mixes. Use silence between tracks for audiobook chapters or voice clips.
Why do the tracks sound different in volume?
Files are often mastered at different loudness. Turn on "Even out the loudness of the tracks" and each one is brought to the same perceived level (-16 LUFS, measured the way broadcasters do) before joining.
Is there a limit on length?
The files are decoded into memory, so very long projects need a lot of RAM. A few hours of music is fine on a computer; on a phone, stay below an hour in total.
Credits
Built on Mediabunny (MPL-2.0), LAME MP3 encoder (via @mediabunny/mp3-encoder) (LGPL-2.0) and FFmpeg AAC encoder (via @mediabunny/aac-encoder) (LGPL-2.1-or-later). OneTooling is not affiliated with these projects.