Why equal power rather than a straight fade?

Because two signals fading linearly against each other sum to less than either one alone at the midpoint, which is heard as a dip of about three decibels right where the transition happens. Gains that follow a sine and cosine keep the summed power constant, so the loudness holds steady through the blend.

Why was my crossfade shorter than I asked for?

The overlap is capped at half the shorter clip. A longer overlap would consume one clip entirely, so the material either side of the transition would no longer be present. The result row reports the capped length whenever that happens.

What if the two clips have different sample rates?

The tool refuses and names both rates rather than blending them. The blend is arithmetic on samples, so different rates would have to be resampled first; the format converter can bring both clips to one rate, after which the crossfade will run.

Which slot should each clip go into?

It matters, and it is the whole point of having two slots. The first clip fades out across the overlap while the second fades in, so swapping them reverses the direction of the transition even though the overlap length is unchanged.

Can I hear it before committing?

There is no preview here, so the finished file is the first thing you hear. That is why the overlap length and the clip choice are worth checking before the run; if the balance is wrong, recreating it with a different length takes only a moment.

Crossfade Creator

You Might Also Need

Audio Fade In/Out

Add smooth fade in and fade out effects

Audio Joiner

Merge multiple audio files into one

Audio Loop Maker

Create seamless audio loops

Audio Merger

Combine audio tracks seamlessly

Crossfade Creator joins two clips with a blend, so the first fades out while the second fades in and the transition holds its loudness. Drop order matters: the first file is the one that fades away.

What is Crossfade Creator?

Choose two files, set the overlap length, and create. The result is a single WAV as long as the two clips together minus the overlap, which is reported along with a note if the requested length had to be shortened.

The slots and settings:

Two labelled file slots, one for the clip that fades out and one for the clip that fades in, each showing the name, duration and sample rate once loaded.
A crossfade length from half a second to fifteen seconds in half-second steps, defaulting to four.
A result row with the download, the total duration and a note when the overlap was capped.

The blend uses gains that follow a quarter sine and a quarter cosine across the overlap, which is why it is called equal power: the two gains squared sum to one at every point, so the loudness stays constant through the transition. A linear crossfade would instead dip by about three decibels at the midpoint, which is audible as a small hole in the music, and this is the difference the name is warning about. Two safeguards are built in. The overlap is capped at half of the shorter clip, because an overlap longer than a clip would consume it entirely and the result would no longer contain the material either side of the transition; the note tells you when that cap was applied. And both clips must share a sample rate, since the blend is computed sample for sample; a mismatch is refused with both rates named rather than silently producing a wrong-speed result. The output is one file long enough to hold both clips except for the overlap, so the total duration is the sum of the two minus the blend. Checking that figure is a quick way to confirm the overlap was the length you intended, and the note about a capped overlap appears whenever the shorter clip could not support the length that was asked for. A mono clip mixed with a stereo one pads the missing channel with silence rather than duplicating it.

What the tool does not offer:

Exactly two clips per run, so a chain of transitions means repeating the process.
No automatic tempo or key matching, so clips of different speeds blend cleanly only if they were meant to.
No preview before rendering, so the balance is judged from the finished file.
No level matching between the clips, so one can dominate the blend.
Only equal power is available; a linear or asymmetric curve is not offered.
Everything is held in memory at once for the two clips, and the output is sixteen bit WAV.

Use it for the transitions it was designed for: joining two songs into a continuous mix, blending an intro into a main section, or stitching two takes together where a straight cut would be obvious. When the files should simply follow one another without a blend, the joiner concatenates them, and when the blend should happen on a single file's own ends, the fade tool is the simpler shape.

How to use Crossfade Creator

Drop the clip that should fade out into the first slot.
Drop the clip that should fade in into the second slot.
Set the crossfade length, remembering it cannot exceed half of the shorter clip.
Press create crossfade and download the blended WAV.

When to use Crossfade Creator vs related tools

Crossfade Creator is the tool for blending two clips across a transition, which makes it the right choice for a continuous mix or a smoothed join. Audio Joiner places files end to end without blending them, and Audio Fade In/Out works on the ends of one file rather than between two. To layer clips instead of sequencing them, Audio Merger plays them together.

Privacy & Security

This tool runs entirely in your browser — no data ever leaves your device. There is no server round-trip, no upload, no logging, and no account required. Your input is processed locally using client-side JavaScript and is never stored, transmitted, or accessible to anyone else. When you close the tab, everything disappears.