toolfree

Audio trimmer

Select a precise section of an audio file and export it as MP3 or WAV. Decoding, trimming and encoding stay in your browser.

Runs in your browser

    Pick an audio file. It is converted on your device.

    Precise cuts inside a consistent working format

    The handles select individual samples in the decoded working buffer rather than whole seconds or one of a thousand approximate positions. Use the arrow keys while a handle is focused to move by one working sample.

    The browser normalises decoded audio to 44.1 kHz before this Tool displays or cuts it. That is an explicit working format, not a claim that the source file was already 44.1 kHz. Boundaries are exact within that buffer, while a source recorded at another rate has been resampled once during decoding.

    The waveform draws the peak in each visible column instead of an average. Averaging can flatten a quiet breath or pause into a straight line precisely where a useful cut point is hiding.

    For one continuous result, set the start and end points and export as before. To keep several parts of the same recording, set a range and choose Add clip, then repeat. The saved clips can be reordered or removed before export; they are joined directly in the displayed order without an inserted pause or crossfade. The same range can be added more than once when it needs to repeat.

    What comes out

    MP3 is encoded again with LAME. If the source was already MP3, M4A, Ogg or another compressed format, the result is a second lossy generation. One pass is usually subtle; repeating it is not.

    WAV stores the working samples without further lossy compression. It is normally several times larger than the source, and a non-44.1 kHz source has still gone through the decoding resample described above.

    Choose WAV when the clip is going into an editor and MP3 when it needs to be small and broadly playable.

    Why the browser reads more formats than it writes

    The browser uses its playback decoders for MP3, M4A/AAC, FLAC, Ogg and WAV. Web Audio does not include a file encoder, so this page writes WAV itself and lazy-loads a self-hosted LAME WebAssembly module only when MP3 is requested.

    Your recording never leaves the device

    The file is decoded, cut, joined when needed and encoded in this page. Nothing is uploaded. The size shown after decoding is the raw PCM held for the operation, so long recordings can use much more memory than their compressed file size suggests.