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Audio Trimmer & Cutter

Trim or cut a section from an audio file locally in your browser, fast and without re-encoding.

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An audio trimmer lets you keep just the part of a recording you want: the chorus of a song, a clip from a podcast, a clean take without the silence at the start, or a short segment to use as a ringtone or notification sound. You give it a start time and an optional end time, and it writes out only that section. It is the simplest and most common audio edit, and it needs nothing more than two timestamps.

Frequently asked questions

Is my audio uploaded to a server?
No. Trimming happens entirely in your browser using a WebAssembly build of FFmpeg. The file is read locally and the trimmed clip is returned as a download, never sent over the network.
Does trimming reduce quality?
No. The trimmer copies the original audio stream into the new file rather than re-encoding it, so the kept section is identical to the source with zero quality loss.
What time format should I use?
Use HH:MM:SS, for example 00:00:10 for ten seconds or 00:02:05 for two minutes five seconds. Enter a start time and optionally an end time; leave the end blank to keep everything to the end of the file.
Can I use this to make a ringtone?
Yes. Trim the section you want (most ringtones are 20 to 30 seconds), then download it. If your phone needs a specific format such as M4A or AAC, run the trimmed clip through the Audio Converter.
What formats can I trim?
Most common audio formats FFmpeg can read, including MP3, WAV, M4A, AAC, OGG, Opus and FLAC. The output keeps the same format and codec as the input.
How accurate is the cut?
Because trimming uses stream copy, cuts align to frame boundaries in the compressed audio. For audio these frames are very short (tens of milliseconds), so for normal use the cut is effectively exact, without the keyframe limitations that affect video trimming.
Can I remove a section from the middle and keep the rest?
This tool keeps one continuous section between a start and an end. To drop a middle section, trim the two parts you want to keep separately, then combine them with the Audio Joiner.
Does it work offline?
Yes, once the page and engine have loaded. The first trim downloads the FFmpeg core (about 30 MB), after which it is cached and works without an internet connection.

About Audio Trimmer & Cutter

This trimmer works entirely inside your browser using a WebAssembly build of FFmpeg, so your audio never leaves your device. It performs the cut by stream copying, copying the existing encoded audio straight into a new file instead of re-encoding it. That makes trimming almost instant even on large files, with zero quality loss: the kept section is identical to the original.

Because it copies rather than re-encodes, the cut points snap to the nearest frame boundary in the compressed stream, which for audio is far finer than for video, so the result is effectively sample-accurate for everyday use. The output keeps the original format and codec, so an MP3 stays an MP3 and a FLAC stays a FLAC, ready to play anywhere the original did.

Times are entered as HH:MM:SS (for example 00:01:15 for one minute fifteen). Leave the end blank to keep everything from the start time to the end of the file. To grab a clip from the middle, set both a start and an end. As with all the tools here, the whole process is private and local, with nothing uploaded.

Why cutting audio is cleaner than cutting video

Both audio and video are stored as a stream of compressed frames, but the two behave very differently when you cut them. Video frames mostly depend on each other: a typical frame only describes how it differs from a nearby keyframe, so you can only cut cleanly at those sparse keyframes without re-encoding. Audio has no such long-range dependency.

A compressed audio stream is a sequence of short, largely self-contained frames, each covering only a few tens of milliseconds of sound. That means you can copy out a section starting at almost any point and it will still decode correctly, which is why stream-copy audio trimming is effectively sample-accurate while video trimming snaps to keyframes. The same cut that would force a video re-encode is free and lossless for audio.

This property is why audio editing felt instantaneous long before computers were fast, and why splitting a long recording into tracks, or topping and tailing a clip, has always been one of the lightest operations in media software. The humble cut, it turns out, is a perfect match for how sound is stored.

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