Audio Mixer & Editor
🔒 Runs in your browser
Export mixdown
One file, sensible defaults — stereo, 44.1 kHz.
Encrypts the rendered mixdown and sends it through a zero-knowledge relay — the server never sees the key. Run the command below on the destination machine to download and decrypt it.
Needs openssl and curl on the destination machine.
Import from a server
Run the command below on the machine that holds the file. It encrypts the audio and sends it here through a zero-knowledge relay — the server never sees the key. It decrypts in your browser and lands on a new track.
Requires openssl and curl on the server.
Import from a URL
Paste a direct link to a public audio file. We fetch it in your browser first; if the site blocks that, a small server-side proxy fetches it instead (public https links only).
A timeline you can arrange, not just a converter
Drop several audio files and each one lands on its own track, stacked down a shared timeline. Drag clips left or right to line them up, grab a clip edge to trim it, press Split to cut the clip under the playhead, and pull the edge handles to fade in or out. Every track has its own volume, pan and mute, so laying a voice-over on top of background music — the most common reason to reach for a mixer — takes a few seconds: music on Track 1, voice on Track 2, drop the music level, done.
Everything happens on your device
Decoding, editing and the final mixdown all run in your browser through the Web Audio API. Your audio is never uploaded — there is no server and no account, which matters when the file is a private recording. So a page refresh doesn't lose your work, the project is autosaved locally in this browser (IndexedDB); it stays on your device and you can clear it anytime with New project. The mix you export is rendered from the same audio graph you hear on Play, so the download matches the preview.
Export one file — or a whole set at once
Simple export gives you a stereo, 44.1 kHz WAV or
MP3 with one click. Advanced lets you pick the channel count,
sample rate and bit depth, tick several formats to export together (zipped), and reach the
telephony family — µ-law, a-law and signed-linear slin, all
8 kHz mono — that Asterisk and most PBX systems expect for prompts and hold
music. Input formats WAV, MP3 and FLAC open everywhere; M4A/AAC, OGG and WebM open only where your
browser can decode them.
Frequently asked questions
What can I do with this audio mixer?
Load several audio files, arrange them as clips on a multitrack timeline, and layer voice over music. You can move, trim, split, fade and adjust the volume or pan of each track, then mix everything down to one file.
Are my files uploaded to a server?
Not by default. Decoding, editing and the final mixdown all run in your browser with the Web Audio API, and there is no account. Your work is autosaved locally in this browser (IndexedDB) so a page refresh does not lose it; it stays on your device until you press "New project". The one exception is the optional Server Transfer: turning it on encrypts your file in your browser first, so only ciphertext we cannot read is relayed to move it to or from another machine — auto-deleted within about 2 minutes.
Which audio formats can I open and export?
WAV, MP3 and FLAC open everywhere; M4A/AAC, OGG and WebM open only where your browser supports them, and M4A can fail on some browsers. You can export WAV (16-bit or 32-bit float), MP3 and telephony formats.
Can I export audio for Asterisk or a phone system?
Yes. The Advanced export writes telephony formats — µ-law (.ulaw), a-law (.alaw) and signed-linear slin (.sln), all 8 kHz mono — that Asterisk and most PBX systems expect for prompts and hold music.
Is it really free, and do I need an account?
Yes, completely free with no account, sign-up or watermark. There are no file-count limits — open the page and start mixing.