A clip that slams in at full volume or stops dead at the end sounds unfinished. The fix is a fade: ease the start up from silence, taper the ending down. It is the difference between a rough cut and something that sounds produced, and the fade tool adds both in your browser.
The short version: load the file, set how long the fade in and fade out last, and export.
How do I fade audio in and out?
Add your file, then use the two sliders. One sets how many seconds the start fades up over, the other how long the end fades down. The waveform tapers at each end so you can see exactly what you are doing.
- Add a file. Drop in an MP3, WAV, OGG or M4A to see its waveform.
- Set the fade lengths. Choose a fade-in length and a fade-out length with the sliders.
- Export. Preview the fades, then save the file as MP3 or WAV.
How long should a fade be?
It depends on the feel you want.
- Short fades, under a second: smooth out a click or pop at the very start or end without changing the feel of the track. Good for trimmed clips and ringtones.
- A second or two: a gentle, natural ease in and out that suits most podcast intros, voice notes and loops.
- Longer fades, several seconds: the slow, drifting outro you hear at the end of songs, where the music gradually disappears.
When in doubt, a one to two second fade at each end works for nearly everything.
Fade just one end
You do not have to fade both ends. Leave one slider at zero and only the other applies. A fade in with no fade out is common for tracks that end on a deliberate hit; a fade out with no fade in suits clips that already start cleanly but need a soft ending.
Fades for clean loops
If your clip is going to repeat, like a ringtone or a background loop, matching fades at the start and end make the join between repeats far less jarring. Pair this with the ringtone maker, which can add fades while it trims your clip to length.
A note on quality
A fade only changes the volume over time, so it does not harm the audio. The only quality question is the export format: WAV stays lossless, while MP3 re-encodes at a high bitrate with a minimal, usually inaudible change. Choose WAV if the clip is going into more editing.
Why it stays on your device
The fades are applied on your own machine. Your file is read locally, shaped in the browser, and saved back to your computer, with nothing uploaded, no watermark and no account. A long track fades as easily as a short clip.
When the start and end sound smooth, open the fade tool and export.