Convert MP4 to MP3 in your browser: drop a video and keep only its sound, as an MP3 that plays in any music app, car or phone. It suits a recorded talk you want to hear on a walk, a song from a concert clip you filmed, or an interview you only need the audio of. Only the audio track is read and decoded; the picture is skipped entirely, and the sound is encoded as MP3 at the bitrate you choose. All of it happens on your device, so even a large video is never uploaded anywhere.
How it works
- Drop the MP4; MOV, M4V, MKV and WebM work too. The soundtrack’s length is read straight away, and a video with no audio track is flagged before you convert.
- Pick the MP3 bitrate: 128 kbps is plenty for talks and lectures, 192 kbps or more suits music. Turn on Trim to keep only part of the soundtrack.
- Convert and download the MP3, named after the video. Several videos at once come back as one ZIP.
Questions
- Does converting MP4 to MP3 reduce the audio quality?
- Slightly. The sound inside an MP4 is almost always AAC, which is already compressed, so making an MP3 means decoding it and compressing it a second time in another format. At 192 kbps or higher that is hard to hear. If you need the sound as close to the original as possible for editing, switch the format to WAV on this page, which adds no second compression.
- How big will the MP3 be?
- The size depends on length and bitrate, not on the video: about 1 MB per minute at 128 kbps, 1.4 MB at 192 kbps and 2.4 MB at 320 kbps. A 30-minute video of 1 GB therefore becomes an MP3 of about 43 MB at the default 192 kbps, and the exact size is shown before you download.
- Can I convert just part of the video?
- Yes. Turn on Trim and set the start and end, by typing times such as 12:30 or by dragging the handles, and only that stretch of the soundtrack becomes the MP3. It is the quick way to keep one song from a concert video or one answer from a recorded interview without converting the whole file.
- Does my file get uploaded?
- No. The models and all processing run inside your browser on your own device. You can verify this yourself: open your browser’s DevTools, watch the Network tab, and process a file: there are no uploads. After the first visit most tools also work fully offline.
- Which formats can it read?
- Anything your browser can decode: MP3, WAV, M4A/AAC, OGG, Opus, FLAC and the audio track of MP4/WebM/MOV video. Output is MP3 or WAV, the two formats that open everywhere.
- Does converting to MP3 lose quality?
- MP3 is lossy, so some information is discarded, though at 192 kbps and above most people cannot hear the difference. WAV output is lossless and correspondingly larger. Converting MP3 to WAV does not restore quality that was already gone.