Audio Joiner

Merge songs and recordings into one file, in the order you choose, with crossfades or gaps. The files stay on your device.

How to merge audio files

Three steps, in the browser.

Add the files

Choose two or more audio or video files, up to 30: MP3, WAV, M4A, FLAC, OGG, MP4 and more. Their lengths and the total are shown.

Order and blend

Move files up or down, set a crossfade (up to 10 s) or a gap of silence, and choose to even out the volume.

Join and save

Join them into one MP3, WAV or M4A, then download it or send it on to the trimmer or the volume booster.

Which join for what

Three settings cover most jobs.

A mix or playlist	Crossfade 3–6 s and even out the volume, so songs flow into each other at one loudness.
Intro, episode, outro	No crossfade, a short gap or none, and even out the volume so music and voice match.
Parts of one recording	No crossfade and no gap: the parts are joined back to back.

What the audio joiner does

Any order

Up to 30 files, moved up or down with one tap. The total length updates as you go.

Crossfade or silence

Blend the end of one file into the next for up to 10 seconds, or put seconds of silence between them.

Even volume

Files from different sources are brought to the same loudness (-16 LUFS) before joining, so nothing jumps out.

Mix formats freely

MP3 with WAV, M4A with FLAC, the sound of an MP4 video: everything is decoded and joined into one file.

MP3, WAV or M4A

MP3 at 192 kbps, 16-bit WAV for results up to 30 minutes, or M4A for iPhone and Mac.

Stays on your device

The files are joined in your browser. Nothing is uploaded and there is no account.

Audio joiner FAQ

Order, crossfades, formats and privacy.

How do I merge MP3 files into one?

Choose the MP3 files, put them in order with the arrows, and press Join. The result downloads as one MP3 (or WAV or M4A). Nothing is uploaded.

Can I combine files of different formats?

Yes. MP3, WAV, M4A, FLAC, OGG and the sound of video files such as MP4 can be joined together; each is decoded and the result is saved in the format you choose.

How do I add a crossfade between songs?

Move the Crossfade slider (up to 10 seconds). The end of each file fades into the start of the next. A fade is at most half as long as the shortest file.

Can I put silence between the files?

Yes. With the crossfade off, set Silence between to add up to 10 seconds of silence after every file except the last.

Why are some songs louder than others after joining?

Files mastered at different levels keep their loudness. Tick Even out the volume: every file is brought to -16 LUFS before joining.

How many files can I join?

Up to 30 at once, each up to 2 GB. WAV results are limited to 30 minutes; MP3 and M4A have no length limit.

Are my files uploaded? Is it free?

No upload: the audio engine (ffmpeg) is downloaded once and runs in your browser, so the files never leave your device. It is free and needs no account.

Can I cut parts out before joining?

Cut each file in the audio trimmer first, or join everything and then trim the result: the joined file can be sent to the trimmer in one click.