How to Extract Audio from Video — Convert MP4 to MP3 Online

Whether it's a lecture, a music video, or an interview — extracting audio from video is simpler than you think. Here's how.

Maybe it's a lecture recording and you want to listen on your commute. Maybe it's a music video and you just want the song. Maybe it's an interview and you need the audio for a podcast. Whatever the reason, extracting audio from video is one of those tasks that sounds like it should be simple — and honestly, it is, once you know where to go.

What's actually happening when you convert MP4 to MP3?

An MP4 file is a container that holds both video and audio streams (and sometimes subtitles). When you "convert" MP4 to MP3, you're really just stripping away the video track and keeping the audio. In many cases, the audio stream inside the MP4 is already in AAC format, which gets re-encoded to MP3.

Does the conversion lose quality?

There's always some quality loss when you convert between lossy formats (AAC to MP3, for example). But for speech, podcasts, and casual listening, you won't notice the difference. If you're dealing with music and you care about audio quality, try to keep the bitrate at 192 kbps or higher.

How to do it

Toolozo's MP4 to MP3 converter works right in your browser. Select your video file, and the tool extracts the audio track and gives you an MP3 download. No software to install, no account to create, and the video never gets uploaded to any server — the conversion happens locally on your device.

If you have video in other formats (MOV, WebM, etc.), the general Video to MP3 tool handles those too. And if you need to convert between audio formats specifically, there's a dedicated Audio Converter.

A note about file sizes

Audio files are dramatically smaller than video files. A 500 MB video might produce a 5–10 MB MP3 file. So if storage is a concern, converting videos you only listen to can free up a lot of space.