ToolPikaHow it works
Your browser decodes the file to raw samples and draws them as a waveform: tall bars are loud passages, flat stretches are silence. That makes it easy to find where a song starts, where someone begins to speak or where the applause ends.
The highlighted area is what will be saved. You can change it in three ways:
- Drag on the waveform. The nearer end of the selection follows your finger or pointer.
- Move the sliders under the Start and End fields. With the keyboard, the arrow keys move them a tenth of a second at a time.
- Type the times. Seconds (
83.5), minutes and seconds (1:23.5) or hours (1:02:03) are all accepted.
Play selection plays exactly what will be saved, fades included, so you can adjust before exporting.
Fades
A fade in raises the volume from silence at the start; a fade out lowers it to silence at the end. Half a second is enough to hide a cut in the middle of a sound, and 2 to 3 seconds gives the gradual ending used on the radio. If the two fades together are longer than the selection, each is shortened to half of it.
Examples
| Task | Selection | Fades | Format |
|---|---|---|---|
| Ringtone from a song | 20–30 s around the chorus | Out 1–2 s | MP3 192 kbps |
| Remove the silence before a recording starts | From the first tall bars to the end | None | Same as the original |
| Clip of an interview to share | The answer you need | In and out 0.5 s | MP3 128 kbps, mono |
| Sample for music software | The exact hit or loop | None | WAV |
Limits
Files up to 200 MB are accepted. The whole file is held uncompressed in memory while you work, about 20 MB per minute, so recordings of more than an hour can fail on a phone; on a computer several hours are fine. The saved file is always 44.1 kHz, 16-bit.
The MP3 encoder is lamejs, a JavaScript port of LAME, used under the LGPL licence.