About the MP4 file format
MPEG-4 Video (MP4) is a video format from which mp3.now can extract an audio track and convert it to MP3.
The guide and converter lists are generated from the live MP3.now catalog, so every conversion shown here is available.
Why MP4 files are used
MPEG-4 Video files combine video, audio, timing and metadata in the .mp4 format.
On mp3.now, MP4 is used as a source when you want to extract its audio track into a standalone MP3 file.
What to know about MP4
Media container
MP4 can hold encoded video and one or more audio tracks.
Audio extraction
Conversion to MP3 keeps the selected audio content and removes the video stream.
Codec support
Successful decoding depends on the codecs stored inside the container.
File size
Video sources are usually much larger than the extracted audio result.
How MP4 conversion works
Converting MP4 decodes the source audio and encodes it with the destination format's codec and selected quality settings.
Lossy conversion cannot restore detail already removed from the source, so keep the original when quality matters.
mp3.now accepts MP4 as an input and converts its audio to MP3.
MP4 compatibility and software support
Playback support for MP4 depends on the device, browser, container features and codecs inside the file.
MP3 output is broadly supported by phones, computers, browsers, editors and media players.
MP4 and related formats
When should you use MP4?
- Music extraction: Save a song or performance as audio-only MP3.
- Speech and interviews: Extract spoken audio for listening or transcription.
- Editing: Create an audio track for an editor or production workflow.
- Smaller delivery: Remove video data when only the sound is required.
Convert from MP4
Use MP4 as the source.
MP4 file format FAQ
What is a MP4 file?
MPEG-4 Video (MP4) is a video format from which mp3.now can extract an audio track and convert it to MP3.
Can MP3.now convert MP4 files?
mp3.now accepts MP4 as an input and converts its audio to MP3.
What changes when MP4 is converted?
Converting MP4 decodes the source audio and encodes it with the destination format's codec and selected quality settings.
Should I keep the original MP4 file?
Lossy conversion cannot restore detail already removed from the source, so keep the original when quality matters.