Step 1: Transfer your MP4 files using the button above or by slide and deposit.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Retrieve your converted M4A files.
MP4 to M4A Conversion FAQ
How do I extract the audio from my MP4 file as M4A?
+
Upload the MP4 file and the converter demuxes the audio stream, then transcodes it to M4A. There is no second video pass — the visual track is discarded immediately so extraction is much faster than a full re-encode. MP4 is ISO/IEC 14496-14, standardised in 2001 and derived from the same QuickTime box layout MOV uses. M4A is an MP4 container carrying audio only, and it is what iTunes, Apple Music and the iPhone Voice Memos app produce.
Is converting MP4 to M4A a second round of lossy compression?
+
Yes, and it is worth planning around. Both formats are lossy, so the M4A encoder is working from audio that has already been through one psychoacoustic pass, and its own decisions compound the first set. At 192 kbps or above the result is still transparent for most listening. If you have a lossless master anywhere, encoding the M4A from that instead avoids the double pass entirely. Almost every MP4 in the wild is H.264 video with AAC audio; the container also legally holds HEVC, AV1 and VP9. An M4A holds AAC in most cases, or Apple Lossless (ALAC) when it came from a lossless rip.
Can I tag the M4A with artist and album information?
+
Yes, and it is a genuine gain over MP4, which has nowhere dependable to store any of it. M4A carries title, artist, album, year, track number and embedded cover art in the container itself, so a music library files it correctly without a manual pass. M4A keeps rich iTunes-style metadata, chapters and artwork intact, and is the native audio format across every Apple device.
What audio bitrate does the extracted M4A use?
+
Default bitrate for lossy M4A is 192 kbps, which is transparent for music. You can override to 320 kbps (audiophile) or 96-128 kbps (voice / podcast / smaller file). The bitrate dropdown is exposed in the advanced options before you click convert.
Will I lose audio quality going from MP4 to M4A?
+
If M4A is lossless (WAV, FLAC), every sample is preserved exactly. If M4A is lossy (MP3, AAC, OGG, Opus), the M4A codec recompresses the source audio — at 192 kbps the result is transparent for almost all content. Going lossy → lossless never recovers detail already discarded.
Does the M4A audio keep the original sample rate?
+
By default yes — 48 kHz audio in your MP4 stays 48 kHz in the M4A output. For CD-burning or legacy player compatibility you can downsample to 44.1 kHz via the sample-rate dropdown; the resampler is high-quality SoX-grade.
Can I extract audio from multiple MP4 files to M4A in one batch?
+
Yes — drop a folder of MP4 files and we extract audio in parallel. Premium users get more parallel workers; on a 50-file batch this is the difference between a couple of minutes and ten-plus minutes.
Will the M4A be tagged with title / artist / album metadata?
+
If the MP4 carries chapter or stream metadata, we copy title / artist / album fields into the M4A container. If not, the M4A comes out untagged — use a tag editor (Mp3tag, Picard) post-export for richer tagging.
How long does extracting M4A audio from a 1-hour MP4 take?
+
Audio demux + encode is fast — typically 5 to 15% of the source duration. A 1-hour MP4 → M4A finishes in roughly 3 to 9 minutes on the standard pipeline; Premium parallelism cuts this further for batch jobs.
Can I extract just a section of the MP4 audio as M4A?
+
Not in this tool directly — extract the full audio as M4A, then use /audio-trim/ or /audio-cutter/ to clip the section. The two-step path is usually faster than a combined operation and gives you precise waveform-level control.
Is my MP4 file private during the audio extraction?
+
Yes — same privacy model as every conversion: isolated workers, no human review, automatic deletion within minutes of completion. The detailed retention window is on /privacy/.
Why does the M4A file have silent gaps where the MP4 had sound?
+
Almost always a wrong-stream selection: MP4 had multiple audio tracks and the demuxer picked an empty or auxiliary stream. Use the advanced "audio stream" picker to select stream 0, 1, 2 explicitly, or target an M4A container that supports multi-track output (FLAC, OGG).
M4A is an audio file format that is closely related to MP4. It offers high-quality audio compression with support for metadata, making it suitable for various applications.
