How do I pick between the three fade shapes?

Linear when the fade should behave exactly as its length suggests, exponential when it should sound smooth, and equal power when the loudness must not dip in the middle of the transition. For a fade at the start or end of a track, exponential is usually the most natural-sounding of the three.

Why is the exponential curve forced to zero at the end?

Because an exponential decay approaches zero without ever reaching it, so the last sample would still carry a small amount of signal and the file would not end in true silence. Setting that final sample to zero guarantees the silence without any audible change to the fade.

What if my fade lengths are longer than the file?

Each is clamped to half the file's duration, so a two-second fade on a two-second clip becomes one second and the two cannot overlap. The report line shows the lengths that were actually applied, which is the reliable way to check.

Can I fade just part of the file?

No, the fades are bound to the beginning and the end. To fade a section in the middle, keep that section with the trimmer, fade it, and join it back, or use the gain tool to shape the level as a whole.

Does fading lose audio?

It reduces the level across the fade span by design, so the material inside the fade is attenuated rather than removed. Everything outside the fades is untouched, and the samples underneath are the original ones multiplied by a gain, not new audio.

Audio Fade In/Out

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Audio Fade In/Out adds a smooth rise at the start of a file and a smooth fall at the end, with a choice of three curves. The last sample always lands on exact silence, so a faded file never ends in a click.

What is Audio Fade In/Out?

Set the two fade lengths, pick a curve, and process. The panel reports the sample counts it actually applied, which can be shorter than requested when a file is very short.

The controls:

A curve selector with linear, exponential and equal power, described on the page in terms of what each is for.
A fade-in length from zero to fifteen seconds in half-second steps, defaulting to two.
A fade-out length over the same range, defaulting to three.
A report line giving both fade lengths as applied, the curve, and the file's duration.

Each curve is a different gain shape across the same span. Linear multiplies by a straight ramp, which is the neutral choice because it is exactly what the numbers say. Exponential applies a power-of-ten curve, which sounds smoother to most ears because loudness is perceived on a logarithmic scale, and it is the one that needs a correction: a pure exponential never reaches zero, so the final sample is forced to zero to guarantee true silence. Equal power uses a quarter sine for the fade in and a quarter cosine for the fade out, which keeps the perceived loudness constant through the transition rather than dipping as a linear fade does — that is the crossfade curve, which is why it suits a DJ-style ending. The three curves differ only in the shape of the gain across the same span, so choosing between them never changes the length of the fade, only how it is heard. Linear follows the numbers exactly, exponential sounds smooth because loudness is perceived logarithmically, and equal power holds the level steady through the transition. Whichever is chosen, the final sample is forced to silence, which is why a faded file never ends in a click. Both fade lengths are clamped to half the file, so the two cannot collide and overlap in a short clip, and any channel count is handled since every channel gets the same gain at the same place.

Where the tool is limited:

Lengths are set by slider in half-second steps rather than typed exactly.
The fade starts at the very beginning and ends at the very end, so a fade cannot be placed partway into a file.
One curve applies to both fades, so the rise and the fall cannot use different shapes.
The values are applied to a copy, so the process is repeatable but not reversible from the result.
There is no visual of the gain envelope, only the report of the lengths applied.
Output is sixteen bit WAV, and no other processing is combined with the fade.

Use it for the ordinary purposes of a fade: softening the start of a recording that begins mid-note, giving a track a musical ending, hiding a boundary where material was cut, or preparing a file that will be looped so its ends are already silent. When the transition is between two different files rather than at one file's ends, the crossfade creator blends them, and when the fade is only needed to kill a click at a cut, a few milliseconds are enough.

How to use Audio Fade In/Out

Drop an audio file onto the panel.
Choose the curve, using equal power if the fade should hold its loudness through the transition.
Set the fade-in and fade-out lengths with the sliders.
Press process, check the reported lengths, and download the faded WAV.

When to use Audio Fade In/Out vs related tools

Audio Fade In/Out shapes the two ends of a single file, which makes it the tool for musical openings and endings and for killing clicks at a cut. Crossfade Creator blends two files across a transition instead, and Audio Trimmer or Audio Cutter produce the cuts that a short fade then tidies. When the goal is a file that loops cleanly, Audio Loop Maker chooses the cut point as well as sealing the seam.

Privacy & Security

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