MP4 or MP3: which format should you save a video in?
Every download screen asks the same question: do you want the video file or just the sound? The answer depends less on quality and more on how you intend to use the file afterwards.
What MP4 gives you
MP4 is a container that holds both a video track and an audio track. It plays on virtually every phone, TV, browser and editing app without conversion, which is why it is the default for saved videos.
- Keeps the picture, subtitles burned into the frame and any on-screen text
- Needed if you plan to re-edit, crop or reuse footage you own
- Larger files: a few minutes of 1080p can be several hundred megabytes
What MP3 gives you
MP3 keeps only the audio track. For interviews, lectures, podcasts republished as video, or a track you own the rights to, it is dramatically smaller and works in any music player.
- Typically 5–15% of the size of the same clip in MP4
- Plays in car stereos and offline music apps that reject video files
- No way to recover the picture later — download MP4 too if you might need it
A simple rule
If you will ever look at the file, choose MP4. If you will only listen to it, choose MP3. When storage is not a problem, saving both takes one extra tap and removes the guesswork.