Fade audio in and out

How it works

1. Add the audio file. Several at once is fine — they all get the same fades.
2. Set how long each fade should be. Three seconds at the end suits most music; half a second is enough to stop a recording ending with a click.
3. Leave the curve on equal power unless you have a reason not to.
4. Press fade and download.

Frequently asked questions

Why not just a straight line?

Because loudness is not linear in amplitude, and a straight line audibly rushes the middle of the fade and lingers at the quiet end. The equal-power curve — a quarter turn of a sine — is what editors use, and it sounds like a steady fade rather than a sudden one.

When would I want the straight line, then?

For a long fade to silence at the end of a track, where the slow tail is the effect you want. It is also what some broadcast specifications ask for by name.

Does it change anything else about the sound?

No. The samples are scaled and nothing is re-timed, so the length, the pitch and everything between the fades are untouched. Re-encoding to a lossy format does what re-encoding always does; choose WAV if that matters.

What if the file is shorter than the two fades?

They are shrunk to fit rather than overlapping, so each gets half the file. You still get a fade in and a fade out; they are just shorter than you asked for.

Is anything uploaded?

No. It all happens in your browser.