How to Turn a Video Into Audio and Save 90% Space
Only need the sound from a video? Convert MP4 to MP3 to shrink the file by 90% — perfect for podcasts, lectures and music. Free guide.
When You Only Need the Sound
A lot of video content is really audio content with a picture attached. Podcasts, lectures, interviews, music performances, webinars — for all of these, the video track is just taking up space. Converting to audio-only can cut the file size by 90% or more.
A 500 MB lecture recording becomes a 30 MB MP3. That fits on any phone, streams instantly, and works with any audio player.
How to Convert Video to Audio
1. Go to Breklo's MP4 to MP3 converter
2. Upload your video file
3. Choose a bitrate (128 kbps for voice, 192–320 kbps for music)
4. Download the MP3
The conversion happens in your browser — the video never uploads anywhere. It works with MP4, MOV, WebM, and other common formats.
Why MP3 Is So Much Smaller
Video files store 24–60 images per second plus the audio. Stripping out all those frames and keeping only the audio track removes the vast majority of the data. The audio quality stays identical to the source — you're not losing sound, just discarding the unneeded video.
Choosing the Right Quality
| Content type | Bitrate | Why |
|---|---|---|
| Podcast, lecture, voice | 128 kbps | Voice doesn't need high bitrate |
| Music, performance | 192–320 kbps | Preserves musical detail |
| Archiving | 320 kbps | Maximum quality |
For spoken content, 128 kbps is plenty and keeps files tiny. For music, go higher.
Need Lossless Audio Instead?
If you're editing the audio in software like Audacity, you may want uncompressed WAV instead of MP3. Use MP4 to WAV for a lossless extract, then convert to MP3 afterward for the final shareable version.
Common Uses
- Save a webinar as a podcast to listen on your commute
- Extract a song from a concert video
- Turn a video lecture into audio for studying
- Pull a voice memo out of a screen recording
For all of these, MP4 to MP3 is the fastest route.
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Frequently asked questions
How do I convert a video to audio only?
Use a tool like Breklo's MP4 to MP3 converter. Upload the video, choose a bitrate, and download the MP3. The video track is removed, keeping only the sound.
How much smaller is an MP3 than an MP4?
Typically 90% smaller or more. A 500 MB video often becomes a 30 MB MP3, because removing the video frames discards the vast majority of the data.
Does converting video to audio lose sound quality?
No, the audio quality matches the source. You're only removing the video, not the sound. Choose 192–320 kbps for music to preserve full detail.
What bitrate should I use for a podcast?
128 kbps is ideal for spoken content like podcasts and lectures. It keeps the file small while sounding clear. Use higher bitrates only for music.
Can I convert video to audio on my phone?
Yes. Breklo works in mobile browsers, so you can convert MP4 to MP3 on your phone without installing an app.