Audio Fade In and Out

How to use the audio fade in and out

1. Choose your audio file.
2. Set the fade lengths and pick a curve.
3. Apply and download.

About this tool

Fades stop a clip beginning and ending with an abrupt click. That click is not imagined: cutting a waveform mid-cycle leaves a sudden jump in amplitude, and a speaker reproducing a step change makes an audible snap.

The curve matters more than people expect, and it is where most simple fade tools go wrong. A linear fade reduces amplitude evenly, which sounds wrong — human loudness perception is roughly logarithmic, so a linear fade seems to drop away quickly and then linger near silence for the whole second half.

Equal power is the default here for that reason. It follows a quarter-sine curve and sits at about −3 dB halfway through rather than −6 dB, which keeps perceived loudness changing evenly. It is what every audio editor uses for crossfades, for exactly this reason.

The logarithmic option drops away faster than either. It suits a fade underneath speech, where you want the music out of the way quickly rather than gracefully.

Even a fade of a tenth of a second removes a click, so if you only want to fix an abrupt start you need far less than you might think.

The result is exported as WAV, because browsers can decode MP3, M4A, OGG and FLAC but can only encode WAV. That means the output is uncompressed and several times larger than a compressed input — a real trade-off, and the alternative would be bundling an encoder several times the size of this entire site.

Common uses

• Removing a click at the start or end of a clip.
• Fading music out under a voiceover.
• Softening the ending of a podcast segment.

Frequently asked questions

Which fade curve should I use?

Equal power in almost every case. It keeps perceived loudness changing evenly, where a linear fade seems to drop fast and then hang near silence.

How long should a fade be?

A tenth of a second is enough to remove a click. One to three seconds is typical for a musical fade out.

Why is the output a WAV?

Browsers decode many audio formats but can only encode WAV. The output is therefore uncompressed and larger; encoding MP3 would mean bundling a codec far larger than this site.