2Enter the start and end time of the part you want to keep.
3Preview the selection and run the cut — the part you keep is copied through untouched wherever the format allows it.
4Download the trimmed AAC file.
AAC Cutter FAQ
Is the part I keep re-encoded?
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Not if the format allows a stream copy — the data you keep is bit-identical to the source and the job finishes in about the time the upload took. Only a frame-exact cut on a format that cannot do it cheaply needs a re-encode.
Does the format limit where I can cut?
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It does. AAC is the MP4-family lossy codec, audibly better than MP3 at the same bitrate and the default for Apple devices. That is precisely what decides whether a cut can be placed arbitrarily or has to land on a structural boundary.
Anything specific to AAC when trimming?
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Yes — AAC carries encoder delay in the container, so a naive cut can leave a few milliseconds of silence that a proper trim removes. It explains most of the "the cut is a fraction of a second off" surprises.
Can I run AAC Cutter on several AAC audio files at once?
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Yes. Upload the set and they process in parallel with the same settings, which is the practical way to handle a podcast series or an album rather than repeating the job by hand.
Does AAC Cutter cost anything?
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No. AAC Cutter is free without an account, and nothing is added to the audio. The upload and the result are deleted automatically about 24 hours after the job, which leaves time to download the result.
Why does a WebM site host AAC Cutter?
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WEBM.to is built around the container the open web actually chose — VP9 or AV1 with Opus audio, decoded natively by every modern browser and needing no plugin, licence or player. Video is the case where extra round trips hurt most — the files are large and every upload costs real minutes. Running AAC Cutter on the same pipeline as the conversions means one upload covers the whole job instead of one upload per tool.
What should I do with the result once AAC Cutter is finished?
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The converter on this site moves video between WebM, MP4, MKV, MOV and the rest, or pulls the soundtrack out entirely, without another upload. Sequencing it that way matters more for video than anywhere else: each re-encode is another generation, so the fewer of them stand between the source and the file you publish, the better it looks.
Is AAC Cutter here the same tool the sibling sites run?
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The engines are shared — the same ffmpeg build with x264, x265 and libvpx, the same workers, the same limits. What a WebM site adds is a view on containers and codecs: which combinations play everywhere, which need a re-encode and which can simply be copied across. It also starts from one fact about the format this site is named after: WebM is VP9 or AV1 with Opus audio, which browsers decode natively but which most desktop editors still transcode on import.
Do I need an account, and does anything get kept?
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No account is needed. Uploads and results are kept for about 24 hours, which leaves time to download the result, and are then deleted automatically; nobody reads, lists or indexes them. Several files in one job need a paid plan.
