Step 1: Deliver your MP4 files using the button above or by place and set.
Step 2: Click the 'Process' button to start the processing.
Step 3: Obtain your converted AAC files.
MP4 to AAC Processing FAQ
How do I extract the audio from an MP4 file as AAC?
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Upload the MP4 file and we demux the audio track, then transcode to AAC. There is no video pass and no quality loss beyond what the AAC codec itself imposes; the /extract-audio/ tool runs the same pipeline.
What audio bitrate does the AAC file use?
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A lossy AAC is encoded at 192 kbps by default. The Audio Quality setting also offers 320 kbps for the best quality and 128 kbps for a smaller file. A lossless AAC (WAV, FLAC) ignores the bitrate and keeps every sample.
Will I lose audio quality going from MP4 to AAC?
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If AAC is lossless (WAV, FLAC), every sample of the source audio is preserved exactly. If AAC is lossy (MP3, AAC, OGG, Opus), the AAC codec recompresses — at the default 192 kbps this is transparent for nearly all source material.
Does the extracted AAC keep the original sample rate?
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By default yes — a 48 kHz audio track inside MP4 becomes 48 kHz inside AAC. If you need 44.1 kHz (CD-quality compatibility) the advanced sample-rate dropdown handles the resample with a high-quality filter (no aliasing artifacts).
Can I extract audio from multiple MP4 files to AAC in one batch?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
How long does extracting AAC from an MP4 file take?
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It depends on the size and length of the file. Small documents and images are usually ready quickly. Long videos take the longest, because most video conversions re-encode every frame.
Can I extract just a section of the MP4 audio as AAC?
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Not in this step — extract the full audio as AAC first, then use /audio-trim/ to clip the section. The two-step path is faster than a combined operation and lets you preview the extracted track before trimming.
Is my MP4 file private during audio extraction?
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Yes. Uploaded MP4 files are processed on our own conversion servers, no person reviews them, and they are never shared. The upload and the converted AAC are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
Why does my AAC file have silent gaps?
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Usually the MP4 carries more than one audio track and the one that was converted is silent or secondary. The converter picks one audio track automatically, normally the main one, and this page has no setting to choose a different track. If the wrong one comes out, remux the MP4 with the track you want first (VLC or ffmpeg can do this) and convert it again.
Does the extracted AAC play on iPhone, Android, or car stereo?
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MP3 plays almost everywhere. AAC plays on Apple devices, most Android phones and Sonos. OGG and Opus need a recent player on iOS but play in Chrome, Firefox and VLC. There are no device presets on this page, so choose the target format your player supports.
