# Online audio editor

Cut, fade, and change the volume of any recording, right in your browser.

A one-track audio editor in the browser: select a part, then cut it, keep only it, fade it, or change its volume, with undo, and download as MP3 or WAV. The file stays on the person's device. It runs in the person's browser, so it's free with no limit, and there's no API call for it. The editor also records.

## How it works

1. Open a recording, or record a new one.
2. Select a part, then cut it, keep only it, fade it, or turn it up or down.
3. Play it back, undo anything, and download an MP3 or a WAV.

## Selecting, cutting, and fading

Drag across the waveform to select a part, or drag the handles at either end. Cut removes the part and closes the gap; Keep only this throws away everything else. Fade in and Fade out work on the part, or on the first or last two seconds when nothing is selected.

A sound wave swings above and below zero. Joining two points that sit at different heights makes a sudden jump, which you hear as a click. That's why the editor adds its tiny fades: each side reaches zero just before the join.

Volume sets a part as a share of how loud it was: 200% is twice as strong, 50% half. To bring a whole file up to the level of podcasts or YouTube, Boost volume measures it and sets it for you.

## For agents

The same edits on a file run as Audo's tools, through the free API or MCP: cut or keep time ranges with `cut_audio` (https://audo.ai/audio-cutter.md), set a whole file's loudness with `adjust_loudness`, and clean up the voice with `enhance_voice` or `remove_noise`. Every tool: https://audo.ai/llms.txt

## Questions

**Is it free?** Yes, always, with no sign-up and no limit. It runs in your browser, so there's nothing to pay for.

**Does my file leave my device?** No. The editor opens your file in your browser and every edit happens there, so it works even on a slow connection. Your file goes to Audo only if you pick one of its tools, such as Remove noise.

**Which files can I open?** Most audio files, such as MP3, WAV, and M4A, and the sound from a video. If your browser can't read one, Convert audio turns it into a WAV that opens anywhere.

**Will my edits click or pop?** No. Every cut gets a tiny fade on each side, a few thousandths of a second, too short to hear, so the two sides meet smoothly. Volume changes ease in and out the same way.

**Can I undo a change?** Yes, every one, as many times as you like. Each edit is kept as a version with a name, such as Cut 4.0 s, so you can go back to the original at any time.

**Is it a multitrack editor?** No. It's one track, made for quick edits to a single recording. To layer voices and music, use Mix audio; to put files one after another, use Merge audio.

**How long can a file be?** Up to about an hour on a computer and about 20 minutes on a phone. For a longer file, Cut audio trims and cuts it on Audo, up to 10 hours.

## More

- This page for people: https://audo.ai/audio-editor
- All tools: https://audo.ai/all-tools