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 M4A file.
M4A Cutter FAQ
Anything specific to M4A when trimming?
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Yes — an .m4a can hold either AAC or ALAC, so lossy and lossless files share one extension and have to be told apart by inspection. It explains most of the "the cut is a fraction of a second off" surprises.
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.
How does M4A Cutter cut the file?
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Concretely, the cut is made on frame boundaries and the surviving frames are copied through without re-encoding, so the audio you keep is bit-identical to the original — no second generation, and the job finishes in about the time it takes to upload. You set the start and end points on the waveform or the timeline and keep what is between them.
Does M4A Cutter cost anything?
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No. M4A 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.
What can I upload to M4A Cutter?
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MP3, AAC, M4A, OGG, Opus and WMA are the lossy codecs handled directly, and lossless sources (WAV, FLAC, AIFF) can go in the same batch. The codec is probed from the stream, so an incorrectly named file still works.
Is there a file size limit on M4A Cutter?
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Yes: free accounts process audio up to 15 MB per file, which at typical bitrates is several hours of material; ffmpeg does the decoding and encoding, exactly as it would on a desktop. That is the most generous cap on the site after video, and audio work rarely runs into it.
Why does a MP3 site host M4A Cutter?
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MP3.to is built around the format that made portable audio ordinary: universally playable, small enough to ignore, and lossy in a way that only matters if you keep re-encoding it. Audio jobs cluster: the same person who needs a format changed usually needs the file cut, levelled or made smaller in the same sitting. Putting M4A Cutter behind the same upload, the same caps and the same account is what turns three tabs into one.
What should I do with the result once M4A Cutter is finished?
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The converter on this site moves audio between MP3, WAV, FLAC, M4A, OGG and Opus, so the output format is a decision you can leave until the end rather than commit to at the start. Doing that after M4A Cutter rather than before means the encode happens once, on the file you actually settled on, instead of twice.
Is M4A Cutter here the same tool the sibling sites run?
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The engines are shared — the same ffmpeg build, the same workers, the same limits. What a MP3 site adds is a point of view about bitrates, about what survives an encode and about when a lossless intermediate is worth the upload time. It also starts from one fact about the format this site is named after: MP3 frames are fixed-size blocks, so a cut lands on a frame boundary and gapless playback markers do not survive a re-encode.
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.
