BrowserTools

MP3 Cutter

Trim audio clips with second precision

By Guga — BrowserTools maintainer, Tbilisi, Georgia Updated 2026-08-12
Free Private No uploads

First run on this page fetches a ~30 MB FFmpeg WebAssembly core from unpkg.com; the browser caches it, so the next cut starts immediately. The clip is re-encoded in the tab and stays on your machine.

What is MP3 Cutter?

Two number fields and a re-encode. The range you specify is decoded out of the source and written as a new MP3 at variable bitrate, so the result is a genuine file rather than a masked region — you can play it, upload it or drop it into anything that reads MP3. Because the end time is floored at a tenth of a second past the start, the fields cannot produce an empty file. Video is accepted as well, and in that case it is the audio track that gets cut, which is often the only part you wanted anyway. Expect the usual encoder artefacts of this approach: a few milliseconds of silence at the head of the new file, and one more lossy generation on material that was already MP3.

Cut MP3, WAV and other audio files to an exact start and end time — for ringtones, samples and podcast edits. Fast local processing, no re-encode where possible.

Private MP3 Cutter In Your Browser

MP3 Cutter is processed locally with client-side JavaScript. Your files never touch a server, and there is no queue to wait in.

Step-by-Step

How to use MP3 Cutter

1

Drop an MP3, WAV, OGG, M4A, FLAC or video file onto the panel.

2

Type the Start and End positions in seconds; both fields step in tenths of a second.

3

Press Cut audio clip. The first run on this site needs a one-off engine download before the encode can start.

4

Play the trimmed result in the audio player, then press Download MP3 to save it under the original filename.

Key Capabilities
  • Recovers a range to a tenth of a second using two plain numeric fields with no timeline scrubbing.
  • Handles video input by cutting the audio track and discarding the picture entirely.
  • Re-encodes to MP3 at variable bitrate quality level 2, so the clip plays in any ordinary player.
  • Enforces a minimum clip length of one tenth of a second between start and end.
Common Use Cases
  • A podcast producer cutting a 4 MB promo down to the twelve-second intro bumper the show opens with.
  • A musician extracting a 15-second loop from a full-length track for use as a ringtone.
  • A student trimming a 90-minute lecture recording down to the one minute their revision notes cover.
Clear Answers

Frequently Asked Questions

Why does the new file start with a moment of silence?
MP3 encoders prepend a small block of silence as priming so that the first real sample lines up with the first frame. Every MP3 begins with it, including the source you cut from. It is a fraction of a frame at 44.1 kHz and is normally inaudible.
Can I cut without losing quality?
Not here. The clip is decoded and re-encoded, so a source that was already MP3 goes through a second lossy pass. A stream copy would be lossless, but the cut point would then have to land on a frame boundary and the file would keep the original's bitrate for a much shorter duration.
What if I set the end before the start?
The end is forced to at least a tenth of a second after the start, so you always get a short clip rather than an error. The field will not tell you it adjusted the value — if you get a tenth of a second back, that is what happened.
Does the first cut need the engine download?
Yes, but only once. The first pass pulls a ~30 MB FFmpeg WebAssembly core out of unpkg.com, after which the browser has it cached and the second cut begins straight away. Your audio is processed in the tab and is not uploaded.