Audio Trimmer

Cut a clip out of an audio file with optional fades, losslessly when the format allows and precisely when it does not.

The Audio Trimmer runs entirely in your browser. Your recording is never uploaded, stored or sent to a server.

Open the Audio Converter

Audio Trimmer について

Cutting audio has one subtlety that video does not. A stream copy is instant and completely lossless, but it can only cut on a frame boundary, so a trimmed MP3 may begin a few milliseconds early or late. Re-encoding lands exactly on the mark and is the only way to add a fade, at the cost of one generation of compression. This trimmer offers both and says plainly which applies, rather than choosing quietly. Seeking happens before the file is decoded, which is what keeps a cut from the middle of a long recording fast even on a large file, and everything runs on your device — a two-hour interview never leaves your machine.

機能

Audio Trimmer の使い方

  1. Drop an audio file, or a video to take its audio
  2. Set the start and end of the section you want
  3. Add a fade if the cut lands mid-phrase
  4. Trim and download the clip

例

入力

Cut 0:10 to 0:40 from an MP3, with a 2 second fade out

出力

30 second MP3 · fade filter afade=t=out:st=28:d=2

The fade is positioned relative to the trimmed clip, not the original file.

よくあるエラーとトラブルシューティング

よくある質問

How do I trim an MP3 without losing quality?
Keep the output format the same as the input and leave the lossless copy option on. The audio stream is copied rather than re-encoded, so there is no quality loss at all — the only compromise is that the cut lands on the nearest frame.
Why does adding a fade force a re-encode?
A fade changes the sample values themselves, and you cannot alter samples without decoding and re-encoding them. A stream copy passes the compressed data through untouched, which leaves no opportunity to apply a filter.
Can I extract a section of audio from a video?
Yes. Drop the video in and the audio track is trimmed and exported on its own — the video stream is discarded, so you get a clean audio file.
What bitrate should I choose for a trimmed MP3?
192 kbps is transparent enough for music on most systems and 128 kbps is fine for speech. Going above the source bitrate never recovers detail — it just makes the file bigger.
Is there a file size limit?
No fixed limit, but everything runs in your browser's memory, so very long recordings use more RAM and take longer. Files of an hour or two are comfortable on a typical machine.

関連ツール

すべての ArrayKit ツール